Widespread Medicaid estate planning would require boomers to confront their own mortality, so that's unlikely. Really it's going to be more like a lottery of those who are "lucky" enough to have their parents die without using long term care, reverse mortgages, squabbling siblings, etc. Most of those lifetimes of accumulation are just headed to the bankers' grindstone, as per the Faustian bargain that created all that on-paper "wealth" in the 80's and 90's.

The houses themselves will for the most part exist - flippers have become adept at putting new builder-grade beige lipstick on the pigs. But they will most likely be corporate rentals, and businesses have become quite proficient at deniable price fixing through the use of software. So even if there is an ultimate lack of demand, I don't expect that the move the needle much.