I don't know who won the debate, as I don't have a working knowledge of formal debate criteria for assessing points in a round to tabulate an overall winner.
What I did pick up, however, is concerning.
It appeared that Trump's narcissism prevented his ego from sitting quiet when Biden spoke critically of him. Though some might say it was Trump's strategy to interrupt and fluster Biden, and the effect of the constant interruptions did take its toll on Biden, understandably, and to the point where Biden started calling Trump names like "clown" and "racist" and "hey man". But I have a difficult time differentiating between where Trump's presumptive strategy leaves off and his narcissism kicks in. Considering that both sides signed off on no interrupting the other, I'm inclined to think that either Trump had no intention of honoring that or his narcissism got the better of him.
A few times Wallace tried to give Trump a question that was an actual opportunity for Trump to easily win a point, but Trump was so defensive with Wallace from the early going that it appeared Trump thought the question was a negative comment/accusation and Trump didn't handle it well. Two of these occurrences, that I recall at the moment, was once when Wallace asked Trump about why he discontinued diversity training, the easy answer that was present in Trump's official statement on it was that CRT is divisive, un-American, and, my comments, it's extremely racist against Whites which I'm sure has been spoken to the President, yet Trump fumbled that easy answer, and the second time was on the violence question where he could have quickly told right-wing groups to stand down and then spent a good minute talking about the truth in detail of the leftist group BLM being the sole initiator of violence throughout America putting the onus on Biden then to ask them to stop all the violence .. yet, he didn't.
Biden's performance wasn't at all spectacular, but he likely scored more "personable" points with the TV audience, despite his use of name-calling.
I know that debate is far from Trump's forte .. but I ended up at the end, with all of Trump's opportunities to easily slay Biden if he would just summon the appropriate detail in his presentation, thinking that either Trump doesn't have the ability to summon detail in such formats .. .. or someone else is running the country, such as Jared Kushner, Mark Meadows, Ivanka Trump .. or maybe a triumvirate of all three, as they clearly have spoken in the kind of detail about the issues that could have easily defeated Biden .. detail that Trump couldn't/didn't summon.
But arguably, a really strong personality is required to get things done, and Trump has indeed gotten a ton of good things done in his 3.5 years. A formal TV debate format does not imitate real White House scenarios where a strong ego, maybe even a narcissist, might be really good at running a company .. or a country .. with the right "triumvirate" assistance .. despite not appealing with a lot of feeling and respect for an opponent.
I don't like the personality quirks, glitches and narcissism of Trump at all .. but I can't argue with his administrations principled results to-date, especially the two Nobel Prize nominations .. and I think that the principled results "trump" the personality issues according to that old wise saying, "principles before personalities".
And, no matter how much "nicer" Biden-Harris might be, they may also thus be weak in international interactions with other nations' strong leaders .. and I know for a fact their socialist economic policy will run us into the ground. I know many viewers are judging the contestants with "would I want my mommy or daddy to behave like this toward me and my friends", a quite inappropriate way to decide who'd make the best President, all presidential tasks considered.
So regardless, I still look at the past four years and the actual behavior results of running the country, both domestically and internationally, especially socioeconomically, that's still my biggest focus, and I really don't care if it's Trump doing it and achieving the Nobel prize nominations or his triumvirate behind the scenes -- the good results remain. And, considering I know what Biden-Harris and the far left Critical Race Theorists that puppet them would do damage-wise to the economy and the social structure of America, I will still be holding my nose on November 3rd and putting my check mark next to Trump-Pence, not "for" them, but as the strongest possible vote against Biden-Harris.