That might not be an entirely wrong assumption to make. An office worker's working hours usually has some amount of slack, and people are willing to adjust their schedule to minimize wait time. No point waiting 25 minutes every day when you can get up 5 minutes earlier and wait basically zero.
The subway doesn’t keep to a strict schedule (it has one in theory but no one would depend on it), and has anywhere between 3 and 20 minute headways (time between trains).
You can sort of kind of get close to 1-2 minutes of slack if you have an app telling you how far away the subway is (CityMapper has this feature), but you can’t really time your sleep or known work hours for making a specific subway.
I mean super-digital people really do. If your train only comes every 20 min, you absolutely have your eye on the app and change the speed you eat breakfast in the morning, or decide you can reply to 4 more emails before leaving work.
There are tons of apps with live train countdowns. They're probably the biggest improvement to NYers quality of life in the past 30 years honestly, with ridesharing in second place.
Schedules are tough for a transit system to keep. Plus you aren't guaranteed to have the same walk to the station every day. Factor in maybe a couple light cycles of signals you need to wait for as a pedestrian to get down to the station, and your travel time on foot to the station can vary by a significant proportion, adding one or a couple three minute light cycles into the mix that might or might not hit for you. I try and anticipate getting to the platform at least 10 minutes before the scheduled train as a result. If I am closer to 5 minutes then I am rushing, feeling late, and stressed, and have missed plenty of trains in moments in this situation before.
You misunderstand. It's not about one seat rides or about schedules. Nobody knows the schedule in NY, the train is frequent enough to not care. But changing lines is basically a statistical 5 min of travel time each time you do it.
Transfers take a very relevant amount of time, even during rush hour when the trains are running frequently. Aside from waiting on the train, which does not keep a strict schedule and can get delayed for many reasons there is the walking time to the other train, which can be a decent amount even in locations where you don't have to exit the subway to transfer. Factoring a minimum 5-10 minutes extra time per transfer is a safe bet.