“These cars, though inconvenient by modern standards, produced less pollution than their gas-driven counterparts” — they were inconconvient by the standards of 100 years ago too, they didn’t have range, and due to the extra weight of water, used *more* energy than the high-compression long-stroke small-bore ICE vehicles that supplanted them. Also, steam vehicle maintenance is higher, because high-wear spots have to be non-ferrous, hence, they’re soft (copper and copper alloys, typically). These are the same reasons locomotives are now diesel-electric.
Uh hum...we also have ball and roller bearings now. Babbot bearings predate those confounded new-fangled things.