I'm sure it's happened way, way more than that, but nobody hears about it for the same reason why practically nobody knows about the ones you listed: being the whistleblower for it is complete professional and social suicide, and anyone who stops to think about it for a second would realize it.

James Damore got fired and called a misogynist by half the world for saying "Hey, maybe google should stop discriminating against men" in an internal email. Imagine what would happen to some guy from Equifax who says publicly "Actually, the reason this massive leak occurred is because our CTO is an unqualified diversity hire woman." Unlike Damore who could at least point to a hiring policy that was openly sexist, this theoretical whistleblower would never be able to prove that the white man who should have been hired for the job would have done better, he might not even be able to prove that that specific woman was a diversity hire even if the company has an explicitly racist and sexist hiring policy. But attempting to blow that whistle would definitely be enough to get the Damore treatment.

And worse than that, even the people close to the problem will never know when it happens most of the time. So the average college grad is... X% stupider due to DEI, and the average professional in any given field is Y% more incompetent. How would you ever assign actual values to X or Y? So when your doctor misses a diagnosis, even if he's a white man, would he have made that diagnosis if he went to the college he deserved to go to? You'll never know. You'll never even know what opportunities you missed due to being a white man in your own life.

Society is worse at every level, and we're losing advances in every field, by lowering us all to a level the stupidest black woman can operate at, and we don't even know what we're sacrificing.