Is enforced when it’s violated. BIshops do not enforce consequences for violations of a schools rules.

If BYU wants a rule that you don’t have facial hair then they can have it, as dumb as it might be.

A bishop should have no part in any judgement of that rule or it’s in enforcement.

The same should be true of any rule which is also a sin. Bishop should play no part in dealing with it at all unless sought out and asked for help by the individual.