"The first assumption is that diversity would supplant quality as the primary goal."

No, it doesn't, because businesses don't want to deal with the persecution and penalties from the government.

And you make the assumption that white males are the ones judging non-white potential employees and businesses as inferior to white.

I've made no secret of my absolute, total and complete hostility toward illegal aliens. I've worked construction since the 70s, and I've worked around literally thousands of them. In this case, familiarity does breed contempt.

Part of my hostility is that I know what the "wetback" Germanic tribes did to Rome by crossing the Rhine to do the "jobs Romans wouldn't do". A bigger part is that, due to my exposure to the reality of illegal alien invaders from south of the border, I know that we haven't been getting the best and brightest, the best workers yearning to breathe free. We've been getting the dregs of their societies.

Yet, the popular myth among the general populace and construction employers (and I know they know the truth), is that "Hispanics" (which to them translates to "illegal aliens") are harder, higher-quality workers than their American counterparts, who are lazy and incompetent. These would be...*white* employers, in large part.

They used this false excuse to assuage their consciences; what they wanted from the illegals was cheap labor by way of circumventing a variety of the labor laws honest businesses had to conform to. (I've already shared how some crooked contractors would put their business in their wives name in order to qualify as a "minority owned business".)

Salazar Roofing advertises on local television a lot. Founded by an illegal alien who only hired illegal aliens. Now that they're a big contractor, that little bit of their past is forgotten. Such is the advantage of crony capitalism. In case it wasn't obvious, Salazar, nor his employees, were white.

Labor laws, such as "equal opportunity" laws, only serve to give advantages to crooks, by creating artificial rules having nothing to do with the necessities of doing business which can then be manipulated to the advantage of the dishonest.

What equal opportunity measures get you is employees who are disciplined for wearing two earplugs rather than one, because they can't hear the PA and supervisors... working next to deaf people. What equal opportunity gets you is hard-working, creative workers having to pick up the slack for lazy, inept, incapable workers, and being chastised for not doing so, so that the company can demonstrate to the government and the sea of anti-business agitators how "diverse" they are in their hiring. And I'm not even basing this on skin color. Various handicaps, ages, sexes, as well as races come into play.

A single example of thousands, which stands out in my mind, of the "quality" of illegal alien labor, btw.

One of our scaffold plank came up missing one day. It was worn and encrusted with mortar, but we needed it, and couldn't find it.
That afternoon, for hours, we heard this repetitious pounding, same rhythm, constantly.
We found our plank... between two houses being built, being "cut" by an illegal who spoke little or no English, chopping away at it with a drywall hammer.
He had been told to get a 2 x 6, 8 ft long. Our planks were 2 x 8, 10 ft long. The boards he was supposed to retrieve were in the garage right next where he was working... along with a table saw that could have cut our plank down in a matter of seconds. HE should be hired because he has brown skin?

Let me correct my faulty memory: our planks were 2 x 10s 8 ft long. He was trimming it the wrong way.

Now a counter example to your bigoted assertion that employers will only hire and promote whites.

My father's masonry firm had gotten a big shopping center; we'd done others, but this was the biggest, and it was going to be his retirement job. It'd give him enough to retire on and turn the business over to my brother and me (which meant to my brother, but that's a personal issue). We had one problem; we had to compete with contractors who hired illegals, something we wouldn't do.
My father chose to hire men on "work-release". These were men who had been in jail, but had earned the right to live in a halfway house, so long as they could stay employed and out of trouble. Not surprisingly, a lot of these men were non-white; none were illegal aliens, but many were black. My father didn't care, so long as the ones he hired were hard-working and competent. Such men he paid the top non-union rate, and treated them as skilled workers deserved; the lazy and incompetent he sent packing.

The general contractors complained to him, one day, that his crew was "too dark". He refused to "lighten" his crew. My father was no civil rights activist, believe me on that. But, first, he wasn't going to be told how to run his business, and second, these men were getting the job done, and his sense of decency wouldn't let him fire them *for the exact opposite reason you would want them hired*.

One Friday afternoon, anxious to start our weekend, my brother and I took a shortcut on a wall. My father quickly caught it, chewed us out, and we spent the weekend rebuilding it the right way.
The following Monday, the general contractor fired us, because they saw us take the shortcut (they were also there seeing us rebuild it...)
The wall was never replaced; we were, by a crew who used illegal aliens. Although ruined, instead of sending the men to collect their pay from the general contractors for that week, my father paid it out of his own pocket. That is, he paid it to the white men, the black men, the brown men, the yellow men, and the red men.

Yes, there will be biases, but without government interference such people will fail to people who prioritize success and productivity.
Natural selection. Think of it as evolution in action.

Because people like you get into government and push priorities other than what makes a business money, honest, decent employers are either forced out of business, or forced to become bastards in order to compete.

"That was the evil, the sort of hell-horror evil that preachers used to scare you with, but you never thought to see alive. Not that the plan encouraged a few bastards, but that it turned decent people into bastards, and there was nothing else that it could do – and it was called a moral ideal!" - Jeff Allen on the 20th Century Motor Company in "Atlas Shrugged"