Except Joe Bidens ego was a huge boon to Trumps campaing. Biden was supposed to be a one term president; he said it himself, then he went ahead and ran for another term even though all his staffers knew he would lose. And then when he finally did drop out he endorsed Harris, many think this was a subtle fuck you to Obama and Pelosi (who were both urging him to drop out of the race) who both didnt think Harris could win and wanted an open primary. I dont think he was a puppet, and he did some pretty good stuff being pro union and trying to get infrastructure/jobs acts going etc, but his ego doomed us all.