@olimould it's just such a complicated situation because it goes up against not only generations of tradition but also institutionalized operations of the political party.
Traditionally, the incumbent president is assumed to be the nominee. It's pretty hard to overcome that barrier of tradition.
Practically, the incumbent president is the head of the political party, with all of the resources of the party to direct. He has a ton of money and resources at his disposal, so any challenger also has to compete against all of that.
That's not necessarily a good thing, but it is the reality, whether we like it or not.
So yeah, I'm sure there are a lot of Democrats trying to oust Biden from the nomination, but it's such a heavy lift to overcome all of that to make it happen.