By what metric should we rate the value of infrastructure like Amtrak's? Should it really be profitability? Maybe I'm not reading the right articles, but I neve

By what metric should we rate the value of infrastructure like Amtrak's? Should it really be profitability? Maybe I'm not reading the right articles, but I never see highway or interstate infrastructure judged by their ability to turn a profit (with rare exception they never do). Rather, they are judged by factors like how many more people can travel, how they decongest traffic, or even the economic activity that they enable. If we take into account the number of cars that are removed from the road, and the economic activity enabled by fast eastern seaboard commutes to financial and political centers, then where does the balance lie for this service? To not sound wishywashy, I bet it looks more favorable.