You may be right but no one I know has ever made every decision correctly. Of course I did not know he was against Trump but that does not lesson his judgment in my opinion. Quite a few people now admit they were wrong about Trump.
Thomas Sowell made some great contributions in economics. I scanned through one of his economics books and it was well done.
He misread Donald Trump. Here is one story he wrote that got a lot of attention at the time.
https://www.nationalreview.com/2015/09/donald-trump-voters-election-egomaniac/