Public bathrooms are getting much better in China. There's been a very noticeable improvement recently, I think tied to a government inspection program.
Granted I was mostly outside of the urban core of tier 1 cities, but most places I went people were constantly smoking in bathrooms, had to BYOTP, and floors were often covered in urine. In some second tier cities like Harbin it was basically squat toilets everywhere, even in the airport lounges.
When did you last visit? I have seen a very big change in just the last year. Most bathrooms have soap and toilet paper now, at least in my random sampling of tier-1 and tier-2 cities.
Smoking is still ubiquitous, though. "禁止吸烟" signs are just completely ignored.