Some highlights for me are that outdoor events have proven to be low risk for spreading the virus. That implies that if you space fan family units 6’ apart, all wear masks, there might be very low risk for the fans at outdoor games.
It sounds like choir practice is a death sentence for the participants. Singing brings out the maximum virus spores, standing close together for an hour or two in a confined space left the majority of one choir all infected from one asymptomatic infected choir member.
Yes, it’s about being indoors and inside: airplanes, in-town mass transit, elevators, basketball games, popular bars, cruise ships, and nearly everything churchish.