Imagine a world where 90% of people are laid off due to AI, do you really think that 90% of people will just sit around and do nothing about it?

No, people, with all their diverse backgrounds, expertise and ingenuity will come together and build what's required for their survival and because of open source technology, they will also have access to the same advanced AI systems as M$.

But what are they using the AI for? Having AI just to have AI will have no value if everyone has it, and the groups that were using developers or writers before (for marketing or software development) will still have no need. What will be valuable about the tool by itself?

Wouldn't the skill in using the tool matter? GH Copilot, so far, has been kind of meh for me - the instances where it produces something actually useful, even after giving it lots of hints, were pretty rare until now. But, two or three generations down the line, it might actually be a tool capable of making a difference. Then, just like with Google when it appeared, people who can work with that tool effectively will be in demand for some time, until either the tool is deliberately broken or something better comes up.