You seem to want to believe government sources too much.
When Amtrak first started (on May Day of 1971, take note), intercity passenger rail service was cut clean in half with no explanation. Aside from the government-owned Northeast Corridor, it was in conflict with all of the private railroads that had formerly owned those services. Average speeds fell to levels not seen since the beginning of passenger rail in the US—except on the NEC, which connected the liberals’ three favorite cities on the east coast.
Between the end of WWII and the end of Amtrak, government regulations had forced private railroads to operate trains at uncompetitive speeds, no faster than 79 mph for passenger trains for the most part; those same regulations combined with taxation forced many railroads to defer maintenance also, and a number of very ill-timed strikes ended up breaking many railroads financially (most notably a strike by the Transport Workers Union against the Pennsylvania RR in 1960, the first that company had ever experienced); and there were other factors such as being forced into agreements to pay firemen for no work when railroads converted from steam power to diesel. Many states ended up subsidizing passenger services, giving them undue control over the railroad companies; and a lot of passenger service was operated under government mandate. (See the pattern of increasing control?)
Conrail cut its way to “profitability”. Once a company finds a way to profit, it ought to stand on its own feet, correct? Instead, this margin of “profit” after balkanizing the railroad network of the eastern seaboard and midwest was a setup for takeover by now-crony-capitalist railroad companies. And it is funny that not only Conrail but other railroad companies rebounded with profit once taxes were repealed and service deregulated.
Claiming that customers had no control over railroads except through federal regulation is garbage. Multiple railroads served just about all towns and competed for customers everywhere in the USA, without regulation; once regulation came to be, those numbers dwindled, creating de-facto monopolies and inviting the induced need for (what?) so-called regulation, and matters such as trackage rights, haulage agreements and “bridge line” railroads had existed long before regulation anyhow. Large trucking companies these days hold monopoly over many sectors of where they serve, and the drivers of trucks are not held to the same legal standards as a locomotive engineer—otherwise we’d lose about 90 percent of them due to being disqualified for driving licenses over speeding (an engineer who overspeeds by 1 mph consistently loses his certification and his job, per government regulations).
You still seem to miss the point about railroads serving industrial customers. A city may be served by five different Class I railroads, but that doesn't mean all of them can access every industrial customer in the city. For example, the major Honda auto plant in Marysville, Ohio is served by CSX Railways. Period. That's it. The railroads invest a ton of money in building the infrastructure to serve large customers like this, and it's not in their best interests to invest in fixed assets like this if they have to deal with competing railroads directly accessing the same customer.