the problem is pretty simple. there's a lot of swing voters who are tired of inflation, etc, and they know that biden isn't up for another term. but they think trump is a piece of shyt, and they didn't really wanna vote for him
biden's performance pretty much greenlit them to say "you know what, fukk this administration. enough is enough. i can ignore trump in the news if he does something about these fukkin gas prices"
Even if they don’t vote for Trump they now will say F it I’m not voting for anybody which hurts Biden