Reagan was a mixed bag. He had a lot of intelligent basic positions, like the Federal bloat, although his Pentagon spending didn't help on the deficits side. And he was shit on the environment and often played loose with the facts, and Carter was a decent military man who didn't really know how to call him out on it.
But Reagan was in fact right about Laffer curve economics and supply side. The Federal Reserve was raping the American public with interest rates close to 20%, and that was beyond ridiculous, so people rightly decided that they'd had enough and looked for someone who'd listen.
I didn't think it was a good thing at the time, but I do now, and it's helped me appreciate an outsider like DT significantly better.