My opinion of Mensa was formed by someone who told me about how, when she was a hiring manager, she once had an applicant who made a point of belonging to Mensa and didn't seem to have anything else she was proud of or had accomplished.

That doesn't mean I am necessarily on board with the fashionable view that IQ is meaningless, but I think to the extent there are people whose IQ is disconnected from their abilities/achievements, it's going to be the ones who are preoccupied with it. So I would think belonging to a high-IQ society would send the wrong message.