Discrimination isn’t always black and white.
People in wheelchairs shouldn’t be discriminated against for an office job, but they’re not going to be climbing ladders as a roofer. In your black and white world are you going to argue that people in wheelchairs shouldn’t have ramp access to offices? Or that because there are ramps into buildings they should be given specialist equipment to enable them to do roofing?
As far as tangential characteristics, there’s a lot of evidence to show that a diverse group tends to have higher performance. But humans are naturally drawn to copies of themselves. So if you’ve got a company that only employs graduates from Oxford University because “it’s the best”, is discriminating.
The lie that is told by the anti DEI believers is that diversity means accepting inferior people. There are many DEI policies and practices that are sensible and practical. 20 odd years ago in the UK it was fairly common practice to have a photo on your CV. These days best hiring practices remove names, genders and race from the CV’s removing innate bias. The only people it hurts are Uncle Fred’s nephew who knows someone and gets a leg up.
Lastly sorry to say it but with bias involved I’m certain that your violinist will be perceived as mediocre no matter how good they are, if you’ve got people who believe that only blond white women can play well. You only need to look at your political views to see that there are those of who believe that Trump is “better” than Harris, because a woman could never be better than a man.