It really is wacky.
I understand why the author made the omission though. I've been on public bus systems in many major US cities and they are entirely the domain of the elderly, handicapped or impoverished.
The NYC bus system though is used by all walks of life, much like the subway itself. In a way I'm glad that the bus system is seen by transplants as less sexy because it keeps the rents in all those neighborhoods not directly serviced by subway lines much cheaper. With Bus Time and a huge fleet [1] of buses, the NYC bus system is often more reliable than the trains.
[1]https://en.wikipedia.org/wiki/List_of_United_States_local_bu...