I think these days, proportion of cash buyers in the last several years was highest in history - inequality did it's job and most people who can afford buying a house, can afford buying it on cash. And before, prices were much lower so most certainly won't fall down back again, forcing banks to invoke foreclosures. So i don't even think rising rates or falling prices may cause a snowballing collapse like they did in 2008. It's permanent - inequality and urban concentration locked next generations out of affordable housing and there's likely nothing that can be done about it.

But in Europe, we lived like that for at least two generations now. This is what a stable state, fully urbanised society looks like. Here, it's typical for someone with a mid-level management position in a bank or an IT company, with million dollar net worth and managing dozens of employees, ride a train to job an hour each day, because they can't afford to rent in the city. And people who live in the city are simply those who's families bought pre-WWI. Or those with a regulated rent contract passed down generations from the 1950s, being an overwhelming portion of the family's effective net worth.