>trying to be diplomatic if the message may not be politically correct
Not exactly; whether my message is politically correct depends on how you generalize it and what groups you apply it to.
You could use it selectively in other contexts and demonstrate either a left or right wing allegiance, but right here and now, I'm talking about people suited to whiteboarding vs. take home tests as the groups.
>that kind of stratification of the market sounds horrible
It's what we've got though, and always have. In your words, "the underlying...reality". Of course we agree things can be improved somehow. I think hiring should be more inclusive, and I think most people would at least give lip service to that.
But if different people are always going to be different, then a hypothetical convergence on a single "fair" standard means telling some fraction of the population they have no place in society at all.
Eliminating whiteboarding, strictly speaking, seems reasonable to object to. It would be unfairly discriminatory. But wanting that to be the only standard also is an extremist position.
If you want to draw a more general opinion out of what I wrote, one of the things on my mind is the general scourge of optimization by tech people who assume the solution to anything is to find the one best answer based on some metric.