Gavra, see Chazon Ish, Emunah Ubitachon, 3-30, who says in no uncertain terms that accusing chachomim of personal bias is considered mal’ig al divrei chachomim. He addresses the passuk you quoted.
You might be right in some cases, because not everyone who carries the title Rosh Hayeshiva is necessarily a proper talmid chochom, but you’ve got to be very careful.