In other words, the very kind of western wealth that you imply is at the heart of the problem!
I'm not so sure that it will change as drastically as all that. China is likely to become much more wealthy, undoubtedly, but the rest will probably carry on much as usual, because that is what business interests invariably determine;
Any serious research on this subject is bound to involve the oceans in some significant way if it is to be taken seriously; we have already discussed the question of provision and distribution of desalinated and purified water where it is most needed - and, indeed to everywhere where syuch water in needed. Whether "electrolysing the oceans" may ever become a practical and productive possibility, I cannot possibly guess.
No, no, a thousand times no! It is LACK of money - or rather lack of money being made available - that is the reason why so little has been done and, as I have said, it is not consumption per se that is at fault but unthinking and inappropriate consumption.
Of course they would - and do - and it is they and their bankers and investors that have put up so much resistance to alternative means of power for so long. That said, I do not believe that any oil company that diversified into, say, solar power and then made thumping great profits out of it would any longer be resistant. Oil companies aren't as interested in oil per se as they are in the making of enormous global profits from consumers. The only problem for them with the solar idea is that there may be a perceived - and perhaps quite genuine - fear that sufficient successful research into this area might end up enabling small companies and private individuals to make their own electricity and become more self-sufficient in energy supplies rather than having constantly to buy more of their energy products.
In sum, the human element probably represents the most important aspect both of the causes and effects of climate change and environmental impacts.