I don't think that's an entirely accurate narrative, but I do think it's probably at least part of this (e.g., that all of the best white people were already hired, while many POC people of equal caliber were not or not making as much). The job market was soaring in 2021 and looking for ways to hire new people without having to pay them more would likely be highly attractive. Now that the job market is not so competitive, there's not as much need to do so if you're just trying to find workers.
In my experience, DEI programs do the opposite. I've seen manager leave headcount unfulfilled because the qualified candidates they found were non diverse and hiring them would put them below their diversity target. If 20% of the workforce is women and your bonus is contingent on reaching 30%, you could recruit at Grace Hopper and try to hire more women. But if that doesn't get you to your quota, you need to hire fewer men to push up the proportion of women.
Edit: another comment on hn says that Bloomberg's methodology was flawed, which seems more plausible to me.
If there wasn't a demand for specifically female engineers they would cost the same as male engineers regardless of the supply because an engineer should be fungible with gender. Unless you think that women have some innate characteristic that makes them better than men?
To fix this sort of problem a wholistic approach is required. Whatever the approach it should apply to all equally so that the market is fair. Offhand, my historic recollection is that STEM generally is traditionally less appealing to those of the female sex (by Science/Biology definition of the phrase), and that there might (rightly?) be a perception of poor work / life balance and career tracks that don't pair well with fulfilling time limited biological imperatives. My personal opinion is that enforced labor regulation that provides sufficient parental leave, work / life balance generally, and generally promotes healthier recognition of employees as humans would be better for society overall.
I also recognize that we're probably not going to get that until the US gets rid of the 'first past the post' madness and adopts a voting system with literally _any_ form of IRV. There just won't be bandwidth for such an issue otherwise. Of said systems, https://en.wikipedia.org/wiki/Schulze_method is my favorite, but I'd start with ANY IRV, they're (offhand) all less flawed than what we've got.
I’m so old fashioned thinking your immutable characteristics shouldn’t be considered for employment.