For example, Amtrak has constant scheduling issues because they don’t have priority over freight trains and many shared chokepoints which are very expensive to fix. If you’re comparing their performance to a system with dedicated right of way or priority scheduling, you need to include the costs spent building that infrastructure to avoid a completely misleading comparison.

Similarly, a system which has high ridership needs less subsidy since it has higher fare revenue for the same base operating costs (think about how those passenger miles change going from 60% occupancy to 80% when the operating cost of basically unchanged). Since the U.S. has massively subsidized car travel and often deliberately avoided rail improvements (think Chris Christie wasting a billion dollars to avoid expanding the congested NJ-NYC connection), there are many cases where American routes have the same operating costs but aren’t as competitive as the same route would be in Europe or Asia because we’ve chosen to subsidize road travel instead. Any meaningful discussion needs to at least acknowledge the difficulties of comparing numbers.