Yabia Omer this has nothing to do with ashkenaz or Sephardic the reason a dress code of a yeshiva bachur or any Ben Torah for that matter in our days is due to simplicity and nothin more then that it is accepted world wide that a Yeshiva dress code is a regular simple dress code once you get into color “it’s not so simple anymore” this is coming from a Sephardic Baal tshuva of 22 years
