Modern capitalism is definitely short-sighted but the railroads are uniquely bad in that regard. They could increase their business and keep marketshare away from road trucking without capital investment but they prioritize operating ratio instead. Every year there are fewer commercial facilities served by rail and it becomes a self-fulfilling prophecy that railroads are in terminal decline.

For sake of argument here are made-up numbers: If you can, by paying some additional labor, with no capex, increase profit by 30% even though operating ratio may slightly decrease while also protecting your business from competitors that is clearly something in the interests of shareholders. If the railroads were run like this I could explain their behavior as standard short-sightedness where they refuse to make the capex investments required to grow their business in the future.

None of this gets into passenger rail service. I don't know that the US market would sustain anything like the numbers railroads did in their heyday but there are absolutely plenty of rail routes that would could have a sustainable and profitable business. With some minor capex they could even do high-speed passenger service to very high profit. Modern 150mph+ train service is stupid cheap and wildly profitable. At that speed you don't have many stops and the travel times are so short your crew labor costs are low. If you already own right-of-way your single most expensive and time-consuming blocker is a non-issue. So far Brightline and CA HSR are seemingly the only ones interested.