Don’t most special interest clubs have some sort of barrier to entry? Is Mensa different because IQ tests are a touchy subject that has been used incorrectly by bad actors? I can promise you that there is no illusion of superiority amongst the mensans I’ve met, we’re all pretty on board with “we’re just good at the things that IQ tests measure” and if anything it just helps a lot of us apply some additional context and understanding to oftentimes difficult childhood memories. Just my two cents from the other side!