For the time being, the Fed has not decided to resell the $2.7 trillion in mortgage-backed bonds it accumulated during the pandemic.

Many of those were potentially toxic leftovers from the great recession. Since the Fed shares a balance sheet with Treasury they can simply be made to "go away" into the ether from which they originated. In any event, they represent a cash glut of reserves seeking safe harbor.

While QE doesn't actually create money in the economy, swapping bonds for liquid reserves, it does effectively increase the available reserves in the private sector. Lacking sufficient bond issues to park the massive number of reserves restored in the banking system by a flurry of bond purchases investors look to the next safest vehicle available. This has historically been the US housing market.

It is my opinion that the Fed anticipated considerably more deficit fiscal spending out of the Democratic administration and Congress than was realized. It would be understandable given the history of such changes in power and the impending calamity facing us with climate change.

A glut of reserves waiting for investment vehicles would have stabilized the bond market if Congress would have met its expectations of deficit spending. They obviously didn't anticipate the level of commitment this new version of Democrats have to neoliberalism and a market based economy.