I think full stadiums of fans are at least 6 months away, if not more.
Socially distanced stadiums could work as well, definitely helps with the revenue issue. No fans in stands means less revenue. 20% full stadiums is at least something.
I am mostly speaking of the sports we watch on TV, professional sports and collegiate football.
College football is significantly important for the budgets of most athletic departments. These athletes will be tested similarly to pro athletes in my opinion. If they can get a consensus by beginning of June, I believe college football will play at some point in 2020. Fans or no fans.
As for high school, rec league, etc. - testing every high school and rec league athlete will not happen on a weekly basis for sure. However, I believe if kids are allowed back to school, all of these sports will happen. If it's safe enough to go to school, then it's safe enough to do sports. My daughter is a competitive gymnast, and they start practice again today. It isn't competition season, so worrying about large gatherings not an issue. Practice is not as often, but they are being very careful and thoughtful. Parents are pretty much not allowed in the gym, only to pick up if their child isn't old enough.