I think you should smile and wish them the best of luck. It’s bad karma to let someone like that get under your skin and equally bad karma to take satisfaction from their problems. And that stuff does come around.
Instead, you should show a little compassion for them because their underwear is showing and they don’t even know it.
It might help to remember that most people we refer to as homeowners are not homeowners at all; they are debtors whose ownership extends only so far as the right to profit or lose on whatever difference exists between the market value of their castle and how much they owe on it. A person who “owns” $20,000 in equity on their house is no better off than a person who “owns” $20,000 of equity in their stocks. That is, unless they’re spending $2,000 extra in mortgage payments every month for the privelege of owning that $20k of equity.