Quality of life is about to take a very hard hit, directly because of the level of inequality [0].
You can't separate these things and expect the world to make sense. When the ultra-wealthy capture too much of the levers of power, and strip-mine all our potential just to get a bit more in a bid for total control, quality of life for humanity suffers.
We've been suffering for it, as I explained above, and we're going to see a lot more of the same. House prices could double in the next 5 years. Even if you own a house or 6 and think that's just great, society will suffer and quality of life will fall.
You might think that owning houses, starting families, clean water, living oceans, a habitable biosphere and healthy division of power don't affect quality of life, but I promise you, they do. And those things are suffering, because of the level of inequality we have reached.
... Let's say, being generous and ignoring a lot of negative externalities, that we actually have improved average quality of life by 10% over the last 50 years. Put that in context - productivity has doubled. Where did all the difference go? ... And what are the beneficiaries of this wealth doing with that money?
The level of inequality is huge, and rising rapidly. That comes with a very serious level of existential threat to life on Earth itself; not just its quality.
You make a lot of claims about the future, but you are guessing. We have no idea. All I hear is fear mongering and hate against people with more than they have.
Fwiw, I think there is a upper bound where inequality starts hurting the average (we aren't near it) however all the solutions I hear are worse than doing nothing. The government forcing equality by taking from one to give to another will never work. It's been tried and it fails horribly.