Page 9 has explained, why investment into fast railfreight is more risky in the USA

Conclusion

When judging about US railroads with European eyes, decisionmaking is best considered to be

a survival strategy in a hostile political environment.
a survival strategy of managers, whose decisions about infrastructure might be judged upon after the next quarterly report.

Instead of getting public money for performing infrastructure upgrades, as in Europe, the railroads pay to the public after doing so, in the form of higher taxes. Historically, these policies have worked as an additional incentive for projects like deelectrification, ripping out the second track of doubletrack railroad, giving up less important lines. It is unrealistic, to expect investment within a setup, that rewards deinvestment.

European express railfreight systems use mostly capacity, that has been added for passenger traffic. Doing it vice versa in the USA has no economic basis. When competing on private infrastructure against trucking on public instrastructure, it is logical to attract the business, that is most compatible to railfreight, and push the excess towards the roads, where capacity and maintenance is a problem of the public. Express freight is best transported by truck, within the logic of existing traffic policies.

Without a major change in traffic policies, towards

public investment into railroad infrastructure, or towards
full cost pricing for road usage of trucks,

it is unrealistic, to expect any US railroad to set up an express freight system. And this also means: No change regarding infrastructure, that could make it easier to run passenger trains.