I see. Printing money to buy new financial assets would also cause greater wealth inequality and populism, although maybe those are seen as benefits to the current administration.
Buying treasuries = the Fed giving money to the US government
Quantitative easing = the Fed giving money to banks
In the case of the US, the entire game is also complicated by the fact that the US dollar has insinuated itself into the global economy. Most critically in oil markets.
Because of this, there are some things the Fed can do (mostly) without the consequences other countries would face.
Look at the wealth inequality increase since 2008. It can mostly be attributed to federal reserve QE policy.