But where does offensive start? People in my youth would’ve called some of our metal band shirts to be offensive.
Yeah, defining that is a bit of a problem. However, I am pretty sure most schools have had prior incidents that set a precedent. I guess some even have specific blacklist (hard curse words, depictions of nudity, revealing armpits etc.) or even a whitelist (sports gear in PE, clothing of major religions)
See, I would’ve never in a million years guessed armpits are somehow offensive to anyone.