If you were old enough, you'd realize the media hated Reagan. The only reason he won against Carter was because the economy was as ****ed up then as it is now, only with higher interest rates.
The reason he beat Mondale was because Mondale was dull as a post. And he had Geraldine as his VP candidate who was Kamala-dumb.
Clinton, on the other hand, lied out his ass about the Bush economy and the media promoted the lie. Clinton was younger and Bush came off as a fuddy-duddy. After 12 years of Republican Presidencies, the nation was going for a change, and there is no denying Clinton's personal appeal
Given the situations, Clinton could easily have beaten Reagan - I would say probably would have - in both 1980 and 1984, but particularly in 1980.
Romney was as much of a stiff as Mondale and the media was on him for breathing. While he would have made a very good President, he had no great appeal to the public. Republicans could have beaten Obama if they'd run someone with a personality and without Romney's arrogance.
Trump, whether you admit it or not, had charisma and a very good record. Covid did him in. Someone like him - a Desantis, say - could have beaten Obama and it's obvious with the number of votes he got in 2020.