Just like I'm required to work if I want money. We each provide a service for compensation. If either of us feels it is not in our best interest we can leave.
Everyone with a double digit IQ knows covid is out there and interaction with other folks is how it spreads. That is a reasonable statement. Therefore, it is reasonable to not be surprised when people who interact test positive. Now, if UT were telling players there is zero possibility of their contracting it, they have liability. If UT were throwing covid parties or somehow trying to get them sick, they would have liability. If they were talking no action to mitigate risk, they might have some liability. Certainly people could file suit, but it does not pass the reasonable man test.