[solipsism]

the idea that anyone could know the optimal level of diversity where human choice is concerned is full of hubris.

It's completely subjective (how you define "optimal"), so why would it require hubris to have an opinion?

[prasadjoglekar]

If it's only an opinion about diversity at the dinner table, then it's not hubris. But if the search for an optimal mix comes from a govt. or quasi-govt. institution then it's no longer an opinion, is it?