That was in the 1700s, and since that time period his observation had been seen to be true. For example trains NEVER paid for themselves via passenger service, they lived and died on freight service, passenger service was required by the States to get the right to condemn land to build a railway, thus trains offered passenger service but it was always a side line, and once the upper classes shifted to cars and planes, such required service went down hill rapidly and abandoned by the railroads.
Streetcars boomed starting in the 1890s but they were mostly built to get people to move to the streetcar suburbs most were built to transport people to and from, but once the lots were sold, the streetcar had a hard time to pay for itself even without the lost of passenger service to the Automobiles starting in the 1920s. When it come to replace the tracks, most cities opt for buses due to NOT having to pay the cost of new tracks, even through new tracks and new streetcars could transport more people cheaper over the life time of the tracks and streetcars then could the buses that replaced them (The buses had lower up front costs but lasted only 1/2 the life time of a streetcars, thus over their life times streetcars were cheaper, but buses were cheaper up front). Please note neither streetcars or buses could pay for themselves for they had no freight service to subsidize them. One Streetcar service that survived the 1950s did so by getting out of the passenger service and conveting to a coal hauling railroad that survived till the 1980s as a diesel operated railroad.
Plane service was subsidized by the Post Office till the 1960s, with the Military building most of the "Airports" used nationally, for the jet fighters could use the same runways as passenger planes. Those airports NOT tied in with an Air Base tended to be built by the local government using tax money not money from the Airlines (New York City's airports tend to fall into this category).
just a comment that Hugh Speed Rail, will be like Sailing Ships in the 1700s, Steam Ships and railroads in the 1800s, Streetcars , buses and even automobiles in the 1900s, they will NEVER pay for themselves and some sort of subsidy will have to be set up or they will just fail.
As to passenger cars, 40% of the cost of highways are paid by real estate and other taxes NOT gasoline taxes (and most of the Gasoline taxes are spent to maintain highways for 80,000 pound trucks, NOT 3000 pounds automobiles).
I bring this up for the survey says people will take high speed rail, and most people will do so if it is free. On the other hand when the issue of price is brought up, the number of people who will opt for trains drops as the price of tickets increase.
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