I don't know if I can handle another Biden vs Trump vote. Please god, let that not happen.
If Dems are smart they'll support someone new, someone younger, articulate, and well spoken. If Trump goes against Biden, I think he'll have the greatest chance of winning and it will be an absolute disaster for America. His first term will be remembered in history books as a cancer, it remains to be seen how far-reaching that cancer becomes, and how long it infests us. I don't know if we would survive another 4 years of Trump.
I think if Trump goes against almost anyone else, he'll lose soundly, though. Biden is just not liked by pretty much anyone, and, well, he's fucking senile. I don't know anyone who didn't cry inside at least a little as they voted for him in 2020... it will be worse in 2024. A fresh face, someone charismatic, I think would be a landslide if the contender is Trump.
If it's DeSantis, though, I'm not sure any Dem would win. I think it would be much more likely the Repubs would win the presidency if they choose DeSantis, rather than Trump. I don't know anyone, nor have I even heard of anyone online, who has become a Trump supporter since the end of his term and all of his shenanigans. I personally know or have talked to a number of previous Trump supporters who he turned off and now admit they were duped and made a mistake. Of course he has a lot of die-hard supporters, some of whom just blindly support anyone they consider anti-establishment regardless of any other reason, and some of whom literally worship him as the second coming of Jesus or something. But that base has only shrunk, and he lost the 2020 election already.