Public toilets are one thing that I really appreciate about living in Japan. It seems like you're never too far away from a toilet - whether it be in a neighborhood park, a roadside parking area, train station, convenience store, etc. And they tend to be pretty clean (at least as far as public restooms go), not something that I dread using like I do many public restrooms in the US.

Japan seems to be just about a best-case scenario, due to the ubiquity of convenience stores, the government's seemingly high prioritization of building and maintaining public toilets, and a culture which places a high value on cleanliness.

It seems like it would be hard to replicate in countries that lack clean and plentiful public toilets without changing the culture first. But reading another comment it sounds like China has made great strides in improving the state of their public toilets due to a strong push from leadership. So it is possible, but again it would start with actually wanting to improve things.