I agree with your overall premise. We need to work on bias.

That said, skin color in NOT our only implicit bias. Height is another. So adding height to the equation won't eliminate skin bias, it will only add another layer.

In addition to that, it's a gendered criteria. Very Few women reach 6 feet.

So that's not going to work. I can't think of a single human characteristic that can't be used to pit people against each other in tribal fashion. The haves and the have nots.

That's depressing.

My personal method of tamping down bias? I think of humans like dogs. There are hundreds of breeds of dogs but they're all dogs. One dog is not better than another dog. They are all products of their environments and training, or lack thereof. Dogs that are quality specimens have had good nutrition, health care, been socialized well, been trained, they've been sheltered, and live in loving homes as part of a group dynamic. You take away any of those things, and you're going to have a dog with problems.

Likewise, race is a false construct. All humans are humans, they're just different "breeds". One type of human is not better than another. See above and I won't repeat myself. You take away any of those things and you're going to have humans with problems. Regardless of any self identifier that can and has been conjured up.