@glomoro idk about piercings, but tattoos used to be/still kinda is associated with yakuza i think? social stigma bcuz of the crime culture and how those groups express themselves visually. no different from how other groups decide to associate with certain characteristics (white supremacists using pepe and the color pink, kpop stans with their clear phone cases and idol polaroids, etc.). these things shouldn't matter, but the groups that associate with these characteristics make employers care. it's for the sake of the work place's image. it's somewhat silly, but also fairly reasonable depending on which side of the coin u look at. difficult to say the extent to which a workplace can decide how you dress/express yourself
i realise this is a really late comment to be added to the conversation, so sorry lol.