As a single example, about 90% of Miami's (Dade County) population will be within 3 miles (many within a mile or two, and almost none past 4 miles) of a station for their "Subway in the Sky" when their 103 mile system is completed.  Local financing is in place, but about 25 years yet to go since the feds cut matching from 80% to 50%.

If the average Miamian lives 1.8 miles from a station, biking to the station, parking or taking a fold-up bike, seems QUITE viable.

Why won't the Fed provide more money? (I know, it's rhetorical by now) Becuse it might help people who aren't rich! No reason the Miami's proposed L can't be built provided it's not ridiculously high-tech. A normal L, yes, but it's a monorail or other amusement park style thing it's aptly named  as it'll be pie in the sky.

One thing. If a lot of transit capacity is needed cheap, there are the old fashioned yellow school bus! No A/C but windows can be opened! That would be the "Cuban method" of ramping up transit cheap. Use what you already have, since the Fed's priority is the No Billionaire Left Behind tax cuts and gratuitous wars.