The thing nearly everyone tries to gloss over when they pull this "Well why don't you let more conservatives in then" is that many front-and-center conservative platforms these days are explicitly intolerant. Why should you be surprised or upset when tolerant institutions seek to reject those? It's a feature of modern civil society, not a liberal conspiracy.
This is the problem with this discussion, I can't stand MAGA ideals, I think they are ridiculous, but you assumed I support it because I used it to point out a flaw in a popular (but flawed) idea.
It's a very real example to show true diversity can't exist in our society across diverse groups.