It's not clear to me why worrying about the widespread socioeconomic impacts of long-term social distancing is "selfish". It strikes me as "rational". I can understand people disagreeing on how long and in what form social distancing ought to continue and I certainly don't have a clear answer in my own mind. But shutting off debate by accusing anyone raising the question of not caring about other peoples' lives is counter-productive.
It's also not clear that a vaccine is the only answer. The purpose of implementing social distancing measures was to "flatten the curve" - to prevent our hospitals from being overwhelmed, not to directly protect each of our individual lives. As the curve flattens and more people develop some level of immunity, as our capacity to test, track and treat improves, and as the economic impact of distancing becomes more severe with time, it doesn't follow that everything must remain in place until there's a vaccine.
This whole situation is much more balancing test and nuance than bright line. August makes a good point above about the potential impact of filling arenas and that's a strong argument (at this point) for either playing in empty gyms or developing arena-specific social distancing measures. But by the same token, COVID is (again, at this point) a minimal risk to the lives of students and athletes and it seems ludicrous to me to concede in April that their lives should be put on hold yet again in the fall. Especially when we're certain to learn much more information over the next month or two about the true characteristics and saturation level of the disease.