Only because their population is so huge. Their Dollar GDP is about 2/3 that of the USA and is 4.5x that of Japan. In a sense it’s set of highly developed urban industrial zones that also has a massive underdeveloped rural area.
My wife is Chinese and last year we went to my father in law's home village in Hebei and stayed with his brother and his family. They have a really nice bungalow they moved into about 10 years ago in a compound right next to the decaying remains of their former house. Almost the whole village has been rebuilt in the last few decades. Hardly anywhere in China is anything like the way it was 30 years ago.
Growing up in Shropshire in the 70s and 80s there were plenty of people in the little villages and isolated farm houses that lived like it was still the 1800s. France too in the early 2000s. Development is never evenly distributed.