That's true for grouping by gender as well, probably even more so. Genetic lottery means some will always be better at a given sport than others of the same gender putting in the same effort. But it's so engrained in our thinking that we don't even perceive it as a problem, instead we tell those with physical disadvantage that they were just not made for a certain sport.

So we are far from competing with perfect here, and being able to pick other attributes to group by should enable us create much more evenly matched groups. I mean, right now we just use one deciding factor for everything and call it a day. And that's before we get into the whole gender discussion.

Regarding the actual formulas, I think we just need to find good tradeoffs between fairness and practicality. Of course even a perfectly fair system will fail if it doesn't work in practice, but I think we can do much better than just using gender in pretty much all cases.