I agree, it does not qualify as a chatzitza. I only mentioned that it was my instinctive reaction to think that it was before I considered and realized that it wasn’t.
And oomis, I agree, mikveh ladies should not make women feel uncomfortable for having tattoos. B”h the women I know do not experience that kind of judgment every time they go to the mikveh, but only sometimes when they are traveling and have to use a mikveh where no one knows them. Also b”h although the mikveh ladies are clearly wrong, my friends just shrug it off and don’t let it bother them.