Participant, maybe I did not travel much lately, but I never met a turban-clad Ashkenazi Rav except on Purim. Rabbis of Bavli and Kohen Godol were earing it, but Ashkenazim seem to have lost the tradition here. Maybe Ashkenazim in Tzefat were wearing turbans?
interestingly, early Muslims required dhimmis to wear yellow patches/yellow turbans, and possibly Christians introduced similar distinct dress for Jews and Muslims as a response.