And, of course, Reagan was infinitely more responsible and reliable than Trump.
This. Reagan was Governor of California for eight years and had been a noted public speaker for many years. He had combined good effective public speaking skills and an ability to govern the seventh (I think) largest economy in the world for the times. He also had campaigned twice for the Presidency and developed an understanding of what the Presidency required by 1980.
To think that Reagan would approve of today's Buchananite GOP is to also ignore the history of Reagan. He also spent considerable time driving out of the GOP the Birch Society (he and William F. Buckley) - the same people who dominate the GOP today. (I'm not saying he was perfect or the types surrounding him were fantastic men. They were not. But as a caliber, they were vastly superior to what we see in the GOP today).