Both the Pfizer and Moderna results have been very positive (Moderna over 95% effective). That is great news.
With that said, 2021 won't be a radical change from 2020. I wish that wasn't the case but it almost certainly will be.
The current vaccine is only for adults. There is no children's vaccine yet. The children's vaccine requires using results from the adult data for development. Hopefully, we can get to phase 2 trials on children by April meaning approval of a kid's vaccine by late 2021.
In terms of rolling out a vaccine - first responders get priority. Logistically, if everything is approved by end of this year, first responders globally can get vaccinated by April. After that, everyone else can start getting vaccinated. The vaccines require 2 shots over 28 days and have difficult storage requirements (kept at below -94F.) Moderna and Pfizer each can only produce approximately enough for 1B people in 2021 (leaving a shortfall of more than half the world's population for 2021.)
As Jeff said, getting people to take the vaccine is critical. We need 80% of the population to take it before it will be effective. Unfortunately, too many people are skeptical of science and medicine and those headwinds will be difficult to overcome.
I can't envision a scenario where GenCon can be done safely in person 2021 even if kids are banned from attending.
Yes, sports are allowing fans. That isn't evidence of things getting better - it is actually part of the problem as to how it is getting worse. The US is in the grips of the worst Covid has ever been here because of complacency and desire to return to normal. You can't socially distance at a gaming table. Even wearing masks, 3-4 hours with the same people who aren't part of your household is a risky behavior during the epidemic.
I want conventions and in-person gaming again myself but we can't do it without making things worse.
For now, we can all help by following the right behaviors and helping others to do the same. When the vaccines are FDA approved, we should all get vaccinated and strongly encourage everyone we know to do the same. Until then, we get good at virtual events and use this as an opportunity to meet distant people virtually that we'd probably never meet in person.
In 1606, Shakespeare had to close the Globe Theater and remain in isolation due to the Plague. He wrote King Lear, MacBeth, and Antony and Cleopatra.
Hopefully, we'll come out of the other end of this with a lot of new ideas and creativity to make 2022 an amazing year.
Fred