>you have challenged me to defend the assertion that equality of opportunity exists
No, I most definitely have not.
I challenge you to demonstrate that interests, cultural values, and other factors that influence professional qualification to be evenly distributed.
This is a sine qua non condition for the claim that "equal opportunity begets equal success" to be true.
If you want to define "equality of opportunity" as all groups being identical in:
- their culture
- their values
- their intellectual interests
- their views on education
...then I ask you: is this really what you want to argue?
Do you really want to deny the existence and legitimacy of these idiosyncrasies that minorities quite vocally cherish? If I were mean-spirited, I might even ask you why you 'hate diversity', but I won't stoop to your level.
If you're instead arguing that the hiring process should be less concerned with competence, and more concerned other things (like skin color, gender and national origin), expect people to disagree with you.
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Edit: some empirical evidence for you to chew on [0]. It points to systematic differences in the professional interests of men and women. I suggest you dismount from your high horse and start looking at cultural differences in professional orientation, as well. Literature abounds.
[0] http://psycnet.apa.org.sci-hub.ac/journals/bul/135/6/859/