TBH because of his physical presentation at the debate. Yeah, it’s short-sighted, but welcome to the public thought process. Whatever is churned thru the latest 15 minute media cycle seems to be what they believe.
Doesn’t matter if he had a cold and was dosed up on NyQuil or whatever; his voice was weak, he stumbled over making coherent sentence multiple times, and he just had a blank, open-mouthed stare when between questions. I’ve had shitty colds and been drugged up with cold meds and I know that feel of being sore, exhausted, hoarse, and disconnected. You just want to go have a lie-down, not a public debate against a raging, insulting, narcissistic asshole. But it takes someone willing to understand all that and give Biden the benefit of the doubt.
There are far too many that start from the “old” part and just attribute everything possible to that which they find disagreeable.