You are making a quantitative argument for a case that can very well be a qualitative one. Your statement is not sound and it does not follow. Maybe it consider this an opportunity to educate yourself in logic?
Ceteris paribus, reducing your hiring pool is a negative.
Can qualitative factors counteract that? Sure, it's possible. But there is no evidence for it here, only assertion. And the quantitative problem is very large, so those factors would need to be very powerful.
Aside from that, it's naive to believe that the qualitative factors will only work in the positive direction. Whatever is gained from excluding the wrong-thinkers could easily be dwarfed by legal or reputational problems, blowback from boycotts or other "cancellation", inability to address the whole market due to a lack of diverse viewpoints, etc.