Okay, I know what you are going to say, and you are right: the wine industry is ahead of most other industries in accepting the existence of climate change, and starting to address its consequences (compare it with the salmon industry, for example). But it seems to me that we have still left it horribly late, given the constraints on viticulture. After all, The United Nations' Intergovernmental Panel on Climate Change has noted that new climate modeling suggests that change is coming much sooner than previously thought.
The basic issue for us is that wine-making relies on grapes, and grape-growing is part of agriculture, which is a practical application of biology; and there are huge parts of biology that do not happen fast — some bits do happen fast, but most bits do not. Many plants and animals grow and breed at quite a leisurely pace, in the big scheme of things. And climate change is happening faster than they can cope (eg. Fire, smoke, heat, drought — how climate change could spoil your next glass of California Cabernet).
In the modern world, we are used to trying to make things happen faster and faster. We often succeed, but that is not necessarily a Good Thing. For example, after the SARS (coronavirus) epidemic in 2002 and the following MERS (coronavirus) epidemic in 2012, a report was published with an explicit forecast of how fast the next epidemic would spread (Predictability and epidemic pathways in global outbreaks of infectious diseases: the SARS case study). Boy, did they get it right, noting in particular the importance of plane travel in making the spread happen really fast. Pandemics used to take years, now they happen in weeks; and we need to adjust to that fact.
So, modern travel accelerates that particular part of biology; and it also helps us with more useful things, like getting food from much further away than we ever could before. But what about other parts of biology? Well, many parts cannot be fast; or, at least, not that fast.
Plants usually take hundreds or thousands of years to adjust to changes in their environment. This is a very specific type of what people mean when they use the word "evolution". In biology, individual organisms themselves do not change. What happens is that there is much genetic variation among any given group of organisms, and some of these variants will be better suited than others to any new situation. These are the ones that will grow and breed, while the others die out. Slowly, bit by bit, that group of organisms will change as a whole, even though no individual within the group changes during its own lifetime.
This natural process all takes time, and lots of it. The world has been through all sorts of environmental changes, including Ice Ages and all the rest of it. These changes have been just as severe as the results of the currently observed climate change, but because they happened slowly the organism groups could adjust. Whole groups of organisms have disappeared through time, of course, not just the well-known example of dinosaurs; but the rest of us have made it, so far.
The issue, then, for the current climate change, is speed. If we are going to continue to live a life-style somewhat similar to our current one, then agriculture needs to be based on organisms that can tolerate the new regime. Many types of agricultural organisms may not be greatly affected by the new conditions, but plenty of them will be; and grapes are among them.
It is for this reason that the wine industry is ahead of much of the game. Regional conditions have always been a vital part of viticulture, in terms of the resulting wine. So, any change in those conditions becomes obvious pretty darned quickly. People cannot help but notice when their wine changes.
Therefore, much of the wine industry has at least taken notice of climate change, and parts of it are actively working on ways of dealing with it (eg. Horticulture researchers find ways to combat climate change in vineyards). What, then, is my point here? It is simply this: the viticulture part of the wine industry cannot change fast, solely because of the time needed for the grape vines. We can be speedy, but they cannot.
Suppose, for instance, we need new cultivars for making wine, ones that can handle the new climate conditions at any given location, and still produce grapes that ripen evenly, with good sugar and acid levels, and excellent flavor components.
Well, we first have to breed them, then we have to trial them in a few vineyards, then we have try making wine from the grapes, and work out the best wine-making style for those wines, and then get the public to decide whether they like them or not. If they do like them, then we have to propagate the vines, and disperse them among the rest of the vineyards, whether for grafting or for new plantings.
There's quite a few years right there — after all, it can take 5 years between planting vines and harvesting a decent crop of grapes. In other words, the wine industry needed to be where we are now about 20 years ago, if not more, if we are going to use new cultivars effectively.
Our current cultivars have been developed over hundreds of years. This is quite speedy compared to the natural process I described above; but half the point of agriculture has been to speed things up by doing them ourselves, rather than waiting for nature to do it for us. We select organisms from among the variants that we can see in nature around us; and we encourage particular organisms to breed, if we think they will have offspring that are of use to us (eg. Champagne growers help cultivate the grape varieties of the future).
This is fast, but it is still slow compared to a human lifespan. The wines I am drinking now are made from cultivars that were mostly derived in previous centuries, rather than during the current one. We have had quite a few human lifetimes to sort out how to make the best wines from them.
The issue, then, is that the speed of climate change is not giving us those lifetimes. We need to make changes right now, not next century. So, we need to speed-up the process of getting new cultivars; and there are biological limits to how fast we can do this.
Mind you, not everyone is pleased with this prospect, anyway. It can take scores of new cultivars to get even one that the wine-drinking public will take to. For example, Robert Joseph (The grape of things to come) has looked at a few recently derived cultivars, and he reports that neither he nor the vignerons nor the wine drinkers are too impressed with some of them. It seems that we may have a ways to go.
However, it is also possible that this response is cultural. The people referenced by Robert Joseph, including himself, obviously assumed the concept of straight varietal wines. Not all wine-making regions favor this approach, notably in Portugal and Spain, but also in Italy. For example, I recently had a wine from Bairrada DOC in Portugal (Quintas de Bágeiras Reserva 1999), which mentions no grape cultivars at all — because the wine is a blend of anything up to six cultivars, none of which you have ever heard of. The way into the future may well be this sort of blending of new cultivars, rather than reverence for a few special ones, as we currently so often do it.
Without moving too far from the idea of new cultivars, another practical alternative is direct genetic modification. We physically move some genetic material from one organism to another, so that the second organism now has a different genotype. That way, we don't have to wait for the organisms to breed, and make new genetic variants, as we simply create the ones we want (or think we do). This is very fast, indeed.
This form of Genetic Engineering is called transgenic genetic modification; and it is opposed by many people, and for good reason. It certainly makes my own skin crawl. The basic issue is that there is no apparent boundary to the ethics of who can do what. If I want fluorescent pigs, then I can have them (Scientists create the world's first glow-in-the-dark PIGS after injecting them with jellyfish DNA); and a lot worse, as well.
A different form of Genetic Engineering is what we call gene editing. We don't actually add new genetic material into the organism, but simply modify what is already there. Some gene-controlled features are actually based on very small changes in the genome, often just the addition or deletion of a single base-pair (the smallest unit of genetic material). If we make these small changes ourselves, then we can add or subtract quite a bit of genetically controlled behavior.
However, this is like anything — all of this can be used for good or evil; and you will get no say whatsoever in which one you get, because it will be someone else doing it (and probably funded by your own government). Genetic Engineering is best banned, in its entirety. The issues are far too complex, and there is far too little understanding about these issues, even among biologists, let alone the public (Key SA wine region leads push to remain GM-free).
An alternative that is available in many geographical regions is to use current cultivars from one region and transfer them to other regions. If Champagne and Burgundy are now too warm for Pinot noir and Chardonnay, then replace them with Cabernet sauvignon and Sémillon. Stick the Pinot noir and Chardonnay in Denmark, where they can now grow quite well. You get the idea — we still get roughly the same wines, and vignerons get to keep growing grapes. What changes is geographical location, not so much the types of wines.
This is still a pretty big change for the wine industry, of course. Our grandchildren will revere Danish wine, even if we don't (yet). I'm probably too old to see it fully, but most of you may not be.
I don't really have an answer to the question posed in the title, other than standard human inertia. We usually don't change anything until we are forced to — if it isn't broken, then don't fix it. However, it has become increasingly clear worldwide that something is pretty seriously broken; and we are now pretty sure that we know what it is. We also have several options for what specifically can be done in viticulture to mitigate the effects of the breakage, along with the obvious global option of trying to slow down (and even reverse) the process of climate change. The future of the wine industry does actually depend on it, whether we turn a blind eye or not.