Wikipedia tells me that the OKC streetcar, post-pandemic, was costing $420k a year, collecting $60k a year in fares, for a net loss of $360k a year. With perhaps 15k riders, that's about $23 dollar per rider, which is absurd. So, I hope the areas it is serving are experiencing a whole lot of additional economic activity and new development, because that's a lot.
More absurd is that a few years earlier, it was free to ride but had 75,000 riders. So the math says $420k a year, collecting $0k a year in fares, for a net loss of $420k a year, for a cost of about $6 per rider. So running things fare-free, they were getting 4x the benefit!
The case for 'free buses' is often questionable--is the reduced travel time reduced stop times worth the reduced fare? But for fixed guideway transit, the calculation is different, because a fixed guideway transit system already represents millions in fixed costs investment. The OKC streetcar was built on the cheap, for $23m. So assuming a (SWAG) of 4.35%, they are already paying a million dollars a year of interest on the debt to build the thing. So its not $420k to operate, it's 1,420k to operate. Which, at 15k riders, is ~$94 a rider. BUT! At 75k riders, that's ~$19/rider.
Once you've built a thing, your best option is to maximize the service you are providing. And the way to do that is to make the marginal cost of people using the service as close to zero as possible. And the way to do that is a pass system. My yoga studio runs $150 a month or $30 a class. And when I'm on a per-class basis, it makes me reluctant to take a class. But while I'm on the monthly pass, I've got every incentive to maximize my use. And that's exactly the logic every fixed guideway transit system should be exploiting, because their marginal cost of additional trip is very small, and their fixed costs very large.
Of course, during the commute peak, transit capacity actually matters and its standing room only. But that's a fraction of the day, and the rest of the day should have discount pricing. Restaurants don't have 'happy hours' because they want you to be happy--but to draw people in during a slack time where they have to 'staff up' prior to the peak, and so they suffer the costs regardless.