At current valuations (Shiller PEs ~40), stocks are disconnected from their income. Therefore, if the Fed tapers harder or even reduces the money supply, it will crash. This leads to a "Ponzi" musical chairs aspect where investors getting in last will have bailed out the ones before them.

> Real estate obviously

Valuations are still heavily influenced by monetary policy, but also by intrinsic scarcity. As space runs out around desirable areas, the ways to acquire are increasingly limited to buying from an existing owner.