Been over 25 years since HIV appeared, and we still have no vaccine for it.
The development of a CV-19 vaccine is likely given the manpower geared towards it, but there remains the possibility that it won't happen soon... or perhaps not at all.
12-18 months being thrown around is generally considered a rosy assessment. The fastest humankind has EVER developed a vaccine was for mumps and took 4 to 5 years.
We need to adjust our mindset. Remember what airline travel was like prior to 9/11 compared to now? Social distancing could be our new normal for some time. How we can reconcile this with the stuff that makes life worth living (e.g. being in the crowded stands of Neyland) remains to be seen.
Personally, statistically I have a low chance of dying should I contract it, and I would otherwise gladly go to a football game and live my life as normal. But i could unknowingly be infected and transmit it to everyone around me while doing so. Those around me could bring it home to their wives, kids, grandparents... others who have a much higher probability of dying.