The problem is that people are judging who "won" the debate by how confident the candidate sounded rather than, you know, how batshit crazy their positions are (Trump) versus how relatively normal their positions are (Biden).
Winning a debate isn't about who's position you agree with, it's about who can create a better argument for their position. I 100% support Biden's position on abortion over Trump's, but I have no idea what Biden was trying to say about the 3 times of Roe v. Wade, while Trump's position (that it should be decided by state law) was completely clear. He also threw in a bunch of lies about how it was an unpopular Supreme Court decision (it was actually a pretty uncontroversial decision I'm 1973), but I understood what he was saying.
I still don't how you could say Trump presented better arguments for anything. He lives and dies by the non-sequitur. He does, however, project 100% confidence in anything he says. He is a man of confidence. A confidence man.
That video says nothing about the actual content of the debate and who "won". It's just saying that Biden was low energy and occasionally incoherent, which I think everyone can agree on. And it's dangerous because that's what Republicans have been hammering on since before the last election.
Yeah...those are the reasons Biden lost. He basically validated every claim that he was too old and senile to be President. Like, I don't know what your definition of winning is here, but being low energy and incoherent is generally considered a bad thing in a debate. You keep bringing up, "content," like there were objective, correct answers to the questions, but that's how quiz shows work, not debates. Debates are all about how you present yourself and your arguments, and Biden completely beefed it on both, while Trump was relatively poised and lucid. It was, by pretty much every metric, a stunning defeat.
Your argument is basically that debates are meaningless performances where no rational person should care about who "won". Which I suppose I agree with, but I don't consider it a good or even neutral thing. Political debates as they exist now are bad and should never be allowed to happen, because all they do is allow the loudest asshole to look good while distracting voters from anything that matters.