> I've seen much cleaner toilets in first-tier China cities than first-tier US cities.

That definitely tracks. LA has a massive unhoused person issue, many of whom with severe mental disorders. You feel a lot that in the commons, especially as you get near DTLA. New York is shabby and dirty in general. More so than a big city usually is. And it's not really a charming shabbiness from an extreme subtropical climate as you get in Taiwan.

The relationship China has with its tier 1 cities is more similar to other Asian countries, like Japan and Korea, than it is to the US.