Abandoning Ukraine to the wolves will not make America richer or safer.
The criticism over the Obama/Trump/Biden journey is probably one of them being too slow to help, or putting shackles on the help, or trying to blackmail Zelensky in Trump’s case.
Also most of that money gets spent with US businesses. It doesn’t get to Ukraine as cash. And from a cold-blooded pragmatic perspective is very cheap for degrading Russian capability.