Trains suck if you don’t have frequency, and because of the population density with a good frequency more than half of the trains will be completely empty and the rest almost empty.
If you out half the funding from car infrastructure instead into train and bus infrastructure this would not be a problem. Induced demand works both ways.
The population in rural areas is so low that no matter how you induce demand, it won’t work.
Look up “interurban railways”. Most towns east of the Mississippi used to have frequent rail service with whistle stops at every farm and crossroads. In addition to passengers these railroads also transported the harvest, Sears purchases, kit houses, even hearses!
Even with unlimited funding, you want to scale the size of the train to the population that could potentially ride on it.
A P42 locomotive pulling 7 Amtrak superliner cars is 700 tons of steel getting 0.4 miles per gallon of diesel. That’s a crapton of mining and drilling and CO2, and it would be incredibly wasteful if it ended up carrying, like, two people at a time.
