TL;DR - at least where I am masks, and probably outdoor minyanim are here for a while.
Wading in to the deep end here - i live two towns over from New Rochelle, where the first frum patient was diagnosed. YINR was the first shul to close for obvious reasons - however, there are only 3-4 yeshivas in our area, and because a lot of the kids attended the same events as the original victim (for example, a lot of the girls in one of my son's grade were at the same bat mitzvah, and several had corona - the first week in March) it quickly spread to the schools and shuls in our area - Scarsdale, White Plains, New Rochelle, Riverdale. The last minyan we had before corona was purim morning, and even that was outside. About a half-dozen people in our shul got sick at that point too, including 1-2 that were hospitalized (B"H, they are doing well now, but 1-2 still not 100%).
Closing shul, however reluctant we were about it. Was a no-brainer seeing how quickly and how many were sick. In late may, our shul re-opened as soon as we were legally able to do so, a few weeks later, we moved some minyanim inside. We hold minyan in our social hall, because the space is open. We simply used a 6-foot table to create aisles and rows - in order to maintain social distancing. People are required to wear masks. The first few weeks were rough, because we were limited to 10 people per minyan.
B"H people are coming back to shul. But at the same time, there are people who're yet to come back. One of our Ba'alei kriyah is very concerned about corona, and isn't ready yet, another member of our shul, was worried about security implications of davening outside, so when we moved inside he started coming, but then felt our HVAC wasn't good enough, so he's now holding out until we upgrade.
At the same time, we have at least minyan of people that are not ready to daven inside yet. This is a partial reason why we're still having minyanim outside - because there are enough of them and we don't want to deprive them of a minyan.
If NY continues to progress in the correct direction, I expect many more people to be coming to shul over the next few weeks in the lead up to the Yamim Noraim. But we're already anticipating our Yamim Noraim crowds might be 25-35% less than in a normal year. (Understand, I am not talking about 3-day a year jews here, these are people who come to shul regularly, who haven't been in shul since purim).