How long should we wait until some here are convinced that our community is safe?
The first step would be offering an explanation as to how those who haven't gotten Covid yet, are protected from it? So far your argument as I see it is that you don't understand it either, but even though everything we know about this virus strongly suggests they are at risk, since you haven't seen a spike in the last few weeks, it must be over even if you don't understand why, and can offer no reasoning why it may not surge again soon.
It will take years before there is sufficient evidence that asymptomatic and mildly symptomatic Covid carriers don't have long term health impacts ch"v.
In fact the data about relapses would suggest those who already contact Covid, like yourself, should be even more careful with their health (eat healthy, exercise cautiously, get vitamin D exposure, etc).
Talking of which, there was what would probably be called a "super spreader event" in my house on Purim. That same yeshiva held a farbrengen in my house again last week (albeit with a slightly smaller crowd).
Reinforces my theory that the reason we aren't noticing a spike in NY is because those who aren't being careful now weren't being careful early on & got it already, and those who were careful early on & didn't get it yet are still being careful.