FWIW, commuter demand has sort of a complicated effect on train routes. Commuters generally want heavy rail to get them from where their housing dollar goes fa

FWIW, commuter demand has sort of a complicated effect on train routes. Commuters generally want heavy rail to get them from where their housing dollar goes farthest to where the highest wage is, and back, riding twice a day, usually over a significant distance. Fast trains, stops widely-spaced so they can hit top speed. This is at odds with local service for residents, who want trains with tightly-spaced stops and care more about frequency than speed. I live in a dense city with largely non-functional rail transit (Baltimore), and IMO part of the problem is that our public transit options can't decide if they want to be commuter rail or local service and wind up being terrible for both (too slow for commuters because it's light rail, too infrequent for local traffic because of the cost of running a bunch of trains out to the burbs).