A portion of the investor class may divest through deregulation as the character of the housing market changes. But the fundamental issue is the presence of the investor class itself. Markets don’t redistribute wealth equitably; they concentrate it. This will continue even if markets acquire new character through deregulation. At best deregulation can change the membership of the investor class. It does not eliminate the investor class.

In other words you are looking at it from a supply side but ignoring the wealth distribution of buyers. Wealth has further concentrated among the richest buyers over the past few years, while the poorest have grown poor, leading to higher prices for everyone. That’s the cause, not NIMBYism, which has been around forever. It’s a wealth redistribution issue not a deregulation issue.