Earlier quoted context omitted.
The New York and Los Angeles metropolitan areas are larger in area than the London metropolitan area The NY metro area is much more populous than London, and the LA metro area is very slightly less populous.
NYC transportation sucks even within areas where the population is very dense. It takes 2 hours to get from Bronx to Coney Island on subway. Plus there are almost daily service disruptions of all kinds. San Francisco's Bart is hated by almost everyone but it is much faster[1]. In fact, I have never taken a slower subway than NYC subway. [1] https://flic.kr/p/7LhwPz
That's a bizarre example. Of course it takes a long time to go from one corner of the city to the other. No reasonable person would be making that commute regularly.