I think he picked moron Biden just because he knew he wouldn’t question it or would accept what he was told.
Makes sense now why he chose Biden. Anyone else would have knocked him out of the big seat quicker.
Having a lame or unpopular VP or successor is sometimes referred to as “assassination insurance.” If people know they’ll get something worse, they usually put up with what they have.
That makes total sense because picking Biden made ZERO sense except he sure couldn’t show up ZERO.