As discussed, all the points that UsualTard makes have merit.
Nevertheless there are other factors at play as well. The reality is that the primaries are a state by state food fight with each one having its own quirks. Generic national polls may or may not line up in way that "they are supposed to" when it comes to state by state realities.
Yes, Trump is out front and that looks formidable when viewed from the national polls.
But it is equally true that DeSantis, an unannounced candidate who has not even started campaigning, is currently ahead in the polls for Iowa and tied for NH. That is not pretty for Camp Trump.
Trump is a tough one to predict because he is subject to major disasters. And then you have to figure out how much they impact the voters down on Main Street versus the hard core maga's. He will run bold and strong for the first part no question. Then you wake up someday, and holy Shiite, what's he stepping into today.
There is the argument that Trump is no longer the guy who "could shoot someone on Broadway and still get elected" or however that expression went. I think he has elements of that remaining amongst the hard core maga, but that it is gone for many pubs now so he will not get as many free passes as he got when he was a rising rock star in 2016.
We shall see.