What types of categories, though? Take gymnastics: do you go with weight or BMI? But how do you handle that men typically have more upper body strength? Take running? Is it weight, height, etc?

Even if it something as simple as BMI or some single number formula how many groupings do you have? 

Let’s say there are 2-3 groups. Who’s watching those events? I assume everyone would watch the “top” group since they’d be more elite. 

Bottom levels prob wouldn’t be watched. 

You could argue men’s sports are watched more but at least some folks like to watch women’s sports. If you just have groupings based on some single number of “eliteness” then who watches the lower levels where there is no gender differences?

As in, some women’s sports might have lower level of “elites” (compared to men) but people will watch women’s gymnastics and running, etc. But who’s going to watch “Level 3” athletes that are, by definition, the least elite?