“The “near monopoly” never existed; that’s propaganda.”
That’s simply not so. American railroads enjoyed a monopoly on long distance travel for at least 50 years, from the Civil War until well after World War I.
There were very few paved roads outside of major cities in 1919 when Captain Dwight Eisenhower led a military convoy across the United States. This at a time when passenger trains were able to travel at over 100 mph between major American cities.
What existed were primitive auto-trails that began to be replaced by the US highway system only in the mid to late 1920s, with much of the construction being done during the Depression. Intercity bus lines then began to rival railroads for passenger traffic.
“Yes; federal regulations don’t make it affordable to build tracks to the current high-speed standards. “
Federal regulation has little to do with it. High speed roadbeds were economically rational when railroads had the passenger traffic to pay for them. With passenger traffic gone and likely never to return railroads are not going to invest huge sums on roadbed that freight traffic doesn’t require.
Federal regulation has everything to do with it. Railroads used to run at 100+ mph with absolute block signaling, which in these days is more labor-intensive. The Interstate Commerce Commission, and later the Federal Railroad Administration, started setting speed limits according to what kind of signaling was on the railroad, putting a major roadblock in the way of private enterprise being able to increase speeds of passenger trains with progression of technology. There are diesel trains that are capable of 150 mph and faster out there these days, but thanks to the regulatory burdens being put on passenger rail, nobody is ordering them.
BTW, one of the first major limited-access divided highways was built by a railroad. The Miller Elevated Highway (later called the West Side Highway) was built by the New York Central Railroad. The city didn’t maintain it after the Central was gone, and they shut it down in 1973 after a truck fell through due to a collapse of one segment; it was fully dismantled in 1989, and nothing replaced it.
The Federal Aid Road Act of 1916 was the beginning of the federal government “competing” with railroads by building highways with taxpayer dollars. Guess who the president was. That act was followed by the Phipps Act of 1921. Never once was the private sector encouraged to engage in such road building; the feds controlled it every step of the way, especially by insisting that the roads not be tolled.