Quotas are never going to work for flight crew - the proportion of female pilots is vanishingly small and, I suspect, similar for non-whites. That's just how it is.
Non-airline flying is "small" business; maybe not in $ terms but in company size terms. Small business works on word-of-mouth and personal recommendation first, advertising etc as a last resort. We don't advertise for sales or recruitment but clients and crew still find us..........