I'm increasingly convinced that awful public restrooms are mostly a North America thing. Travelling in Iceland a few years ago I was shocked at how nice the restrooms at the major gas stations were (N1 stands out). Full-height doors and stall walls, meticulous cleanliness, no weird smells.

At a gas station off the ring road in the middle of nowhere.

Some states have really nice rest stops along the freeway. I think it's variable