Pelosi has been desperate to remove the POTUS from office even before he took the oath. The reasoning has been because she was angry that Hillary! lost, but that's not it.
Not hardly.
The impeachment was a sham, a distraction from what the FBI had, and now we know how corrupt the process has been.
The question unasked is, How many Dems in the leadership are in on it?
Something like this is not for the benefit of just a few people. Other palms need to be greased to get away with it, and that leads to the Speaker of the House, the DNC Committee, and a host of NeverTrumpers who for one reason or the other have worked tirelessly to remove a legitimately elected POTUS. Those involved HAVE to protect Biden, or else the whole thing topples.
How deep does this rabbit hole go?
I suspect this, more than anything else, is the raison d'être for the absolutey insane and unrelenting hatred of DJT. He was widely loved and adored UNTIL he got elected and began his campaign to Drain The Swamp. He threatens their gravy train and threatens prison.