For starters, there's only one way to find out, which appears to be the one way Warren isn't willing to pursue.
More importantly, making it safer to play football isn't the only input the players could provide. All kinds of activities are dangerous. Driving a car, for example. But the B1G didn't ban student athletes from driving a car even though doing so is dangerous. Instead, they relied on the student ahtletes to make that decision themselves.
And like others, student athletes don't make such decisions by only factoring the risks they assume when driving a car. Instead, they also consider the rewards associated with driving a car. And the risks associated with not driving a car. And then make a decision based on all of that information.
But driving a car can be done safely. Can we say the same if two teams of young men decide to play football? Look, I love football too. I have played it and watched it all my life. Nothing feels better than a crisp fall day at Kinnick. But common sense must prevail in this matter sooner or later... or else the virus will.