As far as I am concerned, a sport is a sport. I primarily swam, but I did some track as well, and did and continue to do casual weightlifting. They work different muscle groups but they are all fundamentally the same (all have very low leadership/teamwork opportunities, all require a decent amount of drive and dedication, etc. These are all fundamentally "selfish" sports; most participants will spend most of their time competing against themselves). The other class of sports, the "team sports", are fundamentally different of course but also essentially all the same.

So do universities honestly think they have too many classical musicians, but not enough casual athletes? I don't think so. That seems incredibly implausible. I don't think they are thinking anything at all along the lines of "we better introduce some athletic viewpoints into our student body, lest all the musicians dominate discussion."

I think they are arbitrarily classifying hobbies as "well rounded" or "square" to allow themselves to shape their student body demographics to their liking.