He got removed cause he was losing all 7-8 swing states by a large margin and polls were showing that states like Minnesota could be lost too. And in a presidential year election, votes do not get often split which means that Dems would have been fecked in Senate and House too. So the Dem establishment forced him to stand down.Again.. BUT BIDEN DIDN'T STAY ON.
He got removed because a higher standard applies to him.
Trump displaying equal or greater cognitive issues is not held to the same standard.
Your hypothetical is pointless because it's literally not what happened in reality.
It had nothing to do with standards applying to him, standards really didn't applied to him, and if they were, VP Harris would have used Amendment 25