You also neglected to factor in the economic benefit of people taking a trip they don’t pay for vs not taking that trip at all because they can’t pay. Those people might be taking the train to work, which increases economic activity and value of the entire system, or to school, which is an investment into the future of the system, or to do shopping or eating at restaurants, both of which add value to the system. But I’m also one of those people that think public transit should be free since giving people the ability to freely move around an area can only have net positive outcomes.