Those who can do. Those who can't teach, lecture, scribble, etc!
If economists know so much about economics, why are most of them employees, and not rich?
I prefer letting someone who made billions take the lead.
Not a tough choice at all for me, as I know a bit about worldly economics.
First, many economists have their own business.
Second, some people enjoy the world of academia, doing research, writing and publishing--within this framework, there would be not be a deep understanding of economics without people in academia doing research, publishing and writing. Do you think information about business and economics magically appeared in Trumps brain? Um, no, he most likely read about economics and business from people who publish. The information has to come from somewhere--it usually comes from academia.
Third, hate to break it to you, but most major businesses consult with PhDs on a variety of issues.
Hope this helps, dingus.
ps - yet, Trump was still wrong and Krugman was still right.