Every couple of years he says something this isn’t trash.
I think the fear is he gets on the debate stage with Trump and Trump just out talks him and looks more present and that gives Republicans the argument to say look Trump is crook but he is coherent. Keep in mind I think Biden is coherent, but that isn’t how people assess debates. It’s winners and losers and I can’t think of a president who loss their debates who then won.
With that said, this late in the game, I can’t think of a worse time to start a primary for the Dems. A lot of work has been done behind the scenes to get everyone on the same page and convince the many Dems politicians who are naturally ambitious to let Biden run again unopposed. Opening the gate to a primary now would be the exact chaos that would give the Republicans the cover they need to make them not look like a **** show. Not to mention it would create the natural fault lines between the very different segments of the party that have coalesced around Biden being able to beat Trump.
I say that to say this if these calls for Biden to step down came in February 2023 for him to step down for a primary I could have seen it happening, but it didn’t, and here we are.