True, but voters who are that easy to dissuade can also be dissuaded by weather, or traffic, or waiting in the McDonald's drive-through line so long it eats up the few minutes they had allocated to going to the polls. If people like that are ignoring the national conversation, they're ignoring the national conversation. They're not the all-important "likely voter" in the first place, right?
Insisting that an octogenarian perform feats of strength to reassure us just plays into the strongman narrative that only benefits Trump. Frankly, even though I thought his performance as a debater was abysmal, I saw no indication that his comprehension was diminished in the slightest. But we keep insisting that he "do something" to prove that he isn't what he is, which is older and slower than he used to be. The president's job isn't to trade barbs with a deranged smoothbrain, which is fortunate, because Biden isn't good at that anymore. But he's still a savvy negotiator who continues to deliver some measure of policy wins. Isn't that what we actually want?
If this election comes down to who projects more youth, then you're all correct, and this is a lost cause, because time cannot be undone. We will only be disappointed if we keep holding our breath and wishing that he will show up to a podium and be the loudest/wittiest/most energetic. But that's the wrong criterion to focus on IMO.