I think athletics CAN teach kids discipline and a "hard work pays off" attitude. And don't underestimate the positive impact of sports bringing people together as fans. Even if it's just giving a father and son something to talk about.
I think the really beauty of sports is later on, the memories.
You get 4 years to make those memories and then it is gone, there is no going back. Hell, the idea of going back is such a big idea that movies are made about going back to HS.
I don't remember the scores of all the games I was in but I remember screwing around in the locker rooms, or on the bus. I remember wearing my jersey to school and how it seemed so cool and pep rallies that I was either a part of or that me and friends would ditch to go eat or play video games or drive around.
Unless you are on an amazing team you won't have a ton of memories about wins and championships.
We usually close the door to the coaches office when our players are coming in from practice but sometimes it is open and hearing those HS kids talk about practice, school, girls, jobs, college all that stuff, it is pretty cool to hear, as much we like to complain that things are so different now, they really are pretty much the same for HS students.
Also, side note, if your kid is in HS speech, they might as well be in a soft core porn movie. I had to do asst speech for one year and those speech meets are just a bunch of HS kids doing a speech and then coming back to the cafeteria area and making out.