Earlier quoted context omitted.
People who build housing create value. People who manage properties create value. People who speculate on properties do not create value.
Why are people selling real estate assets to speculators for less than they are worth?
The problem isn't that speculators are evil people but rather that the "arbitrage" they are doing is fueled by regressive housing policies. Increasing the efficiency in the housing market exposes the fundamental housing problem. After all, it can't just be that speculators are snapping up properties, there must be buyers that are willing to buy properties from the speculators, otherwise the speculators lose money. Those buyers don't even need to think that the house is overpriced, the house could genuinely be a good deal for them.