I think it’s pretty clear that having a large portion of the city spend an hour a day packed together with 80 or so other people is going to increase transmission from a droplet spread disease.
Yes, subways are crowded, but so is everything else in NYC. As for why NYC is doing much worse than other comparably dense cities worldwide, my thesis is that it's a failure at all levels of civic participation (federal, state, local, and even residential and commercial proprietors) to be proactive in counteracting the spread of coronavirus.
That’s rush hour. Let’s not kid ourselves.
(I'll also point out that you picked literally the busiest station on the entire system to use as an example.)
The thing about the subway is that we all try to hold onto a pole or bar, total vectors for the spread. It’s not just an obvious case of being near each other, we’re forced to touch the same surfaces so we don’t collide every 30 seconds.
https://www.cnn.com/2020/04/30/opinions/eye-opening-south-ko...
The case study covers infections in a 19-story mixed commercial-residential building. First case was reported on March 9, 2020. The office seating diagram provided in the article shows extended (10 min or 1hr not sure), very close proximity spacing physically is the main reason for the spread.
Note that this was a call center so people were sitting and talking without masks on for extended periods.
* On March 9, one day after the first cases were reported, the entire building was closed. Testing was performed almost immediately on 1,143 people (workers, residents and a few visitors) with rapid results available to those affected and the team working to control the situation. The testing showed that 97 people (8.5% of those occupying the building) were infected. Most of the cases were women in their 30s and almost all (94 of the 97) worked on the 11th floor of the building, in the call center.*
I counted colored seats in the diagram and found 84 people in the call center got infected.
I think NYC got hit particularly hard because of subway cars. Enclosed in nearly airtight space for 10 - 30 minutes at a time.
I agree that everything is more crowded in NYC, but the only thing I can think of more crowded than a subway car is a nightclub. Estimating from ridership numbers, the average New Yorker rides the subway 15-30 minutes per day. The ceilings aren't even that high, just the number of people per unit volume is incredible.
One of the case studies I saw showed it spreading on a long distance bus between people sitting four rows away from each other.