Scott Alexander has a good summary of what went wrong with the former mindset (fill the job with the qualified candidate becomes mimic the population at large or else): https://www.astralcodexten.com/p/book-review-the-origins-of-...

The problem with DEI is that it did, in fact, turn into a policy of racial quotas, only the quota-ness was denied even though the threat of legal action was omnipresent.