Honestly I don't think it is. However a lot of opponents to removing country caps are always concerned with this. Hence I was saying if anything country caps may be justified for family based GCs. There is no viable argument for them to remain for employment based GCs.
Diversity?
Does diversity mean you have to have proportional representation for everyone on earth? Or does diversity just mean having various different ethnicities or national origins within the country? Does constraining some very large groups actually skew the demographics anyways?
At least according to company’s HR, yeah, it means an equal proportion.