My case is built on the empirics that corporate investors are a very small fraction of the available houses for sale. Notice the stories you're reading about places where corporations are disruptive: they're in thin markets. A corporate investors can totally (if temporarily) fuck up the prices in a single subdivision. But unless they can do that across a broader market, they don't have meaningful pricing control.
My claim would be that in any any of the top 10 markets by transaction volume (just to pick a handy metric out of the sky; you could choose others), corporate investors are literally a nonfactor.
They don’t have to buy to fuck up the market. They just have to bid. If there’s low inventory, people that actually need to buy a home are forced to beat/match the bidding.
They can also target just specific areas of specific major metros and there are ripples throughout the entire market.
The housing “market” does work the same as the stock or commodity markets. People aren’t buying an intangible share. They’re buying this specific and unique house and if they’re told “we just got a cash offer for $50k over ask”, they may be tempted to beat it. That doesn’t happen when people buy AAPL. The shares are fungible.
There’s only empirical evidence of their buying activity. We’ll never know how many deals they bid the price up on but didn’t buy. This auction like quality is evident in any market like this; watch Storage Wars and one disinterested buyer will bid up the price just to fuck with his competing bidders.