Trump was popular with a certain segment of people. Like the kind of person who doesn't understand how to constructively manage a business and thinks that being "the boss" revolves around firing people, presumably because they're generally on the receiving end of it. If you weren't in that segment, occasionally seeing him was more like "oh wow, that guy is still around?"

There is no conspiracy here. Running for president gave him widespread attention, where he became relevant to many more people - relevant in a negative way. And while the actual facts have become heavily politicized, that Trump's policies are so beneficial to Russia and China is itself quite damning, regardless if he himself is aware of it or whether it's merely being susceptible to foreign agents in his orbit.

For reference where I'm coming from - I was telling my aghast blue tribe friends in 2016 that Trump had a good shot at winning and was talking about a lot of longstanding problems other politicians would not. The problem is that it was, and continues to be, just empty talk.