Or as I'd put it, let's state the goal clearly.
We could all pretend that we all knew what "unbiased" was, as long as we lacked mechanisms for putting numbers on these things. We could meet our fuzzy conception of the biases with our fuzzy conceptions of what "unbiased" ought to be and we could all speak back and forth to each other praising the virtues of how unbiased our models of the universe are, and there was no way to dig in any farther to see if we were all actually saying the same thing.
Now we can put numbers on it. So, do it. What's the goal? Be clear. It's a program. Anything you can clearly specify can be done. It's not useful from an engineering perspective to define the goals entirely by examining each model in sequence and deciding on the spot that it's not "unbiased"; give us a definition in advance, so we can build a model to try to fit it.
Once the goal is stated clearly, the engineering work becomes much easier. We can even iterate on the goals. I'm not asking for perfection on that front on the first try any more than I ask for it anywhere else. But there's been enough of these articles that just point at a specific point in the space of models and call that point problematic. Move on the to next phase. What wouldn't be problematic? Exactly? At least take a stab at it instead of trying to make vague insinuations so we can iterate on the stab.
Nor am I trying to prejudge what those answers will be. It isn't necessarily the case that the only possible answer is to just slam in 50/50 numbers for the genders (or whatever other constant values you want for whatever other genders you want). Though if that is what you want, do it, and see what happens, and iterate from there. But what other things can be tried too?