> massive investments made by hedge funds, private capital, REITs which does not appear to be addressed at all?

If corporations buying houses was actually affecting the purchase market prices, then we'd see an equal effect on rental prices going down. A corporation can't live in a house, so they'd be renting it out. If these evvvill corporations were keeping houses vacant just to screw over regular hard working folks, resulting in no effect on the rental market prices, then we'd see it in the vacancy stats. But that's never actually mentioned by housing conspiracy theorists because the vacancy stats show that the areas with highest prices have extremely low vacancy rates, because demand for housing is so much higher than supply, because not enough housing has been built.