Contact sports are dangerous. Team contact sports lead inexorably to the commodifaction of human health. That doesn't mean they're not worthwhile. I think they are, and that the risks are worth it. We should always be looking to improve safety, though, so long as it doesn't infringe on the soul of the sport.
I don't think contact sports are worth it. Or rather, I fail to see what a contact sport like football brings to society over a contact sport like basketball, which while still dangerous in the sense that leg injuries are common, at least has a low chance of fucking with someone's brain.