Extensive use of the subway is what sets NYC apart from all other cities in the US, and it was the main vector. NYC should have been much more diligent about cleaning the subway and limiting concurrent access. I understand due to the sheer volume and necessity of subway use the chosen policies may have been the best. But the subway has been overcrowded and near the breaking point for years and little was done to maintain the system before COVID.
And remember, if the subway capacity was increased, subway ridership would likely increase as well, as it becomes a more appealing mode of transport.
What NYC really should have done is shut down businesses on March 1 instead of March 15. But... I don't know, I think that's a lot to ask of politicians. The public would not have responded well to schools being closed and restaurants being shuttered. We needed a wake-up call.
By contrast, I feel like Florida, Georgia, etc have really had that wake-up call, and have chosen to flout it anyway. I don't have much sympathy.
You have other countries where subways service are still running with no major breakouts. ny has resumed service, and no major breakouts either.