There is no cellular data in the NYC subway? I had to look it up online and apparently there is but coverage is quite patchy. That's very surprising to learn, NYC being one of the most developped and richest cities in the world. By comparison, and from my experience, the Parisian metro has excellent coverage.
But I’ve never felt comfortable opening a laptop on the NYC subway. It wasn’t about the safety that OP describes. It was about the culture and the physical configuration (facing middle with strap hangers vs facing front/back). It just didn’t feel right in the subway.
I do miss the MetroNorth Bar Car! I could drink and code and it was jovial.
An intercity train with wifi/cell service (and tea!) is an incredible focussing function as well. You got 3 hours and a beautiful not too distracting view. Go!
P.s. I also suggested to Stephen that he gets a Nathan Fielder “laptop harness” for his subway work..? Has anyone tried this?
[0] https://ask.metafilter.com/316039/Ideas-for-workspaces-pleas...
Why you ask?
I'll tell you. He edited videos on the NY subway using his Lenovo(?) laptop with a massive extra battery hump in the back, which he used as a handle to hold on to with one hand while he typed with the other.