Thank you for the downvote kind sir. I get that you disagree with me, but isn't civil discussion the way to go? That's what Reddiquette is all about, but I digress.

Anyway, this system was dependant on the good time lasting forever. The vast majority of these properties were probably bought with a mortgage, and these people were simply over-leveraged to a pretty insane degree. But rescissions happen all the time, and business owners should take that into account. You can't start a business during an economic boom I'd the business model is only sustainable with limitless growth because that simply doesn't happen.

As for housing markets, AirBnB undoubtedly had a hand in reducing supply, but I would argue that zoning laws have a much larger role to play. By limiting the amount of high density, affordable housing, you're going to see an inevitable spike in housing prices. That's the main reason housing cost in San Francisco have skyrocketed. You have a surge in demand, but home owners are a powerful voting block. They don't want to see apartment buildings being built because that would impact the value of their own home, which they obviously want to appreciate.

Ideally, if we didn't restrict plots to single-family housing, the market would realize that there is a surge in housing prices. Investors would realize that they could make money but building high density housing and selling cheaper units in much larger quantities. This would bring down housing prices across the board, and is exactly what the invisible hand of economics is supposed to do.