Yes the bias is huge, and doubly bothersome because even attempts at inclusion are framed from the perspective of the currently powerful. I look at how many big-name white male devs on my twitter feed make a big show of trying to raise up others. Yet it's a wildly disproportionate group of conventionally attractive women in their early 20s making corny 5-second comedy clips that are getting all the attention. That, or pushing model minority stereotypes that are more about making the man sharing them look good. Heaven forbid they include a woman with the same 5-pack of hoodies wardrobe and under-the-chin, poorly lit selfie they have, just because she's actually a good dev.
While I can understand the resistance to selection criteria if it removes more nuanced decisions necessary in building a team, I can't think of a better way to offset those biases you describe. Those biases are extreme and clearly, left to our own devices, we do a bad job addressing or recognizing them.
The general premise i have usually heard is something along the lines that selection in the work environment often involves nepotism, networking, "cultural fit" and other under-handed ways of biasing the results. This is both unfair and a self-perpetuating prophecy. The explicit action of forcing a selection criteria will hopefully break the cycle and "reset" the system to an equal playing field.