I agree there's no good answer. But this election is unique because both candidates are so unpopular.
Biden is poling below "generic Democrat" in swing states. There's literally an incumbency disadvantage. So normally, yeah, it would be a bad idea for someone to drop out this close to the election, but in this circumstance I just feel like not being Trump or Biden and not having their baggage might be a bigger advantage than more time to build a campaign.
"I'm under 70, not Biden or Trump, and didn't sponsor a genocide

" would probably get more votes than Biden's

campaign events
Dude somehow has an infinite supply of tweets of random LGBT activities we're supposed to care or be outraged about
But say something about kids being massacred in Gaza and you get told to stop being a crybaby