As the WT loves to use the OT (Hebrew scriptures for them):
2Sa 10:5 Messengers told David what had happened, so he summoned them, for the men were thoroughly humiliated. The king said, “Stay in Jericho until your beards have grown again; then you may come back.”
As said, it is a controls issue based on Western (American) values and customs. Same as wearing a suit. In the middle, even today, men were using long robes. Jesus was. Same as using a tie....useless and actually, wearing a suit and tie might give a distinguished impression but at the same time, can disguise who you really are on the inside. Sales men look like that but can they always be trusted?