I have seen a few of these with similar story lines and realized we are living it right now. They have the best healthcare, the best food, the best everything and most of us are a few dollars from disaster. That scares some of us to death literally from all the stress it causes.
I think there will still be many places that will be livable even if the temperature rises to +10, such as Nothern Canada and Russia. So it seems probable “rich” people could be able to have their own colonies their, though it’s probable rich will have a different meaning then, maybe more about water and food than numbers on the internet. Our species is far from endangered, it’s rather our civilisations that are, the bad and the good in them.