If the bubble burst, it will burn people which bought a whole gamut of properties and let it sit empty for the appreciation of inflated value first. We saw that in the 1980ties before when people with 3 to five properties, invested and even rented out could not pay the combined mortgage and had not only to take the loss, but walk away from it.
In the mid nineties, when house prices took a dip, people were able to wait out the time until their houses bought at excessive pricing drifted back up trough the loss period when general inflation brought pricing to the winning level again.
Now it will get interesting: The period where general inflation, cars, food, energy and not at last income drifts up to make these million and multi-million inflated house sales look like normal might take way too long, unless we get hit by food and goods hyperinflation and the leapfrogging wage increases as in the late 1970 years. Not good if income stagnates and prices raise.