> From what I've been told, the east and south coast cities are the most modern in the world. It's hard to imagine - decline.
I've been to Shanghai a couple of times, to Hong Kong once... also nearby Singapore... and I can confirm: it looks very much like a futuristic place compared to your average European or American city, though slightly dystopian due to all the surveillance/single-party.
But I think the reason for that is simple: almost all infrastructure you see around has been built in the last few decades, so it's all really modern... you go to London and it's the total opposite... the London Underground is like 150 years old!! It's not gonna look very modern no matter how much you improve it.
But of course, without a thriving economy you wouldn't build such colossal projects like China has been doing... anyway, if we start seeing all this beautiful, modern infrastructure starting to crumble, or places where infrastructure still hasn't been modernized not getting any improvement, then I think we can start to talk about decline - but China seems to be very, very far from that right now.