iirc the NYC subway is only about 40% subsidized by fares. I’m happy to pay more in taxis for it to exist and subsidize lower income residents. There are huge economic benefits to the city that you’re not factoring in.

Not everything has to be directly money making.

If anything, the Bay Area needs significantly more public transit. BART in particular is mostly useful between cities, in my experience. You can’t go from the mission to cow hollow or dog patch to north beach, let alone anywhere to the ocean.

Also, subways don’t have much (if any) marginal cost per passenger. The issue isn’t cost but ridership. Ridership will increase with utility, which requires political will, which does not exist.

SF could be so much more.

If you think subways have no marginal cost per passenger, you should consider Zeno’s paradox more