This is an interesting question, one I've pondered for a while.
This is speculation, but here's what I believe:
Let's assume wealth follows a Pareto distribution, with the single parameter alpha determining the shape of that curve, and thus the resulting income inequality.
I think that growth of real economic output / GDP probably has a maximum for some alpha, above which, increased inequality slows down growth. I suspect it also declines BELOW a certain alpha since it offers fewer people with extreme capital to the market capable of making moonshots.
However, that doesn't mean growth stops, and I suspect the people high on the curve have little incentive to change. I'm not sure though. Is it better to have ownership of X percent of wealth, and greater relative wealth, or X-e percent of wealth, less relative wealth but more growth?
Now... ostensibly, I don't think there's likely to be a 'peak'. It would defy the assumptions of a market. If housing prices rise so high there aren't enough buyers, prices would fall. However... famously, certain billionaires have been known to buy up all the houses around theirs at exorbitant prices to enhance privacy. So I suppose you could still see vacant housing, but no fall in prices.
That said, in general, quality of life would decline for lots of people. We'd see a lot more roommates and extended family groups living together to make it affordable. People in US cities used to do that a lot actually, and we might see a return to that.
There has historically been a floor though, where below that, things are so bad that people don't have much to lose by taking up arms, dragging rich people into the street and cutting their heads off.
Another angle in modern times is that we are seeing such a precipitous drop in birth rates in the West, that I suspect we'll start to see countries compete for people interested in having children by creating financial incentives and friendlier conditions to do so.