Did you actually read the Bell Curve? Your criticisms of it seem like that of someone who didn’t read it, but simply read a review from someone who shares your ideology.
And your criticism of ideological diversity reads like a typical left wing fascist. Everything you think is correct, therefore anyone who disagrees is not only wrong, but some kind of ‘ist’, whether that be racist, sexist, whatever.
Ideological diversity is acknowledging that people can have different opinions without being evil. You’ve demonstrated that you just don’t get it.