Derech haMelech should study the Gemoro in the early part of Tractate Bobo Basro:- Someone who dresses in a Rabbi’s Garb and isn’t holding by that level, the Gemoro has some less than nice things to say of that individual. However, someone who is of caliber of a Rabbi, but humbles himself to a business/lounge suit, the Gemoro speaks nicely of this person’s meekness.
But Derech haMelech’s application of foolish to the names he appended this appelation to, is very inappropriate to say the very least. No-one is looking up to any of those individuals on his list because of their white shirt, but because of the Torah knowledge they have been Zochim to reach & disseminate.