Emphatically no, China is a long way from being “so developed.”
My father was born in this village. I took this photo this year. Not to say that China doesn’t have development; here is a T5/6 city.
And this is a T1/2 city. Note all examples are from the same province (Hubei).
The reality is that China has invested a lot in distributed development, but it is mostly urban development. Most rural villages are not developed sufficiently, even if they now have road, power, and water. Developed countries generally differ here because developed countries have had time to apply development throughout the ecosystem, whereas this is only applicable to a developing country’s focus areas.
China has come a long way, but a developed country it is not, let alone a superpower on that basis.
A showcase of development in one photo. Mud brick = pre-1970s to at least Qing era. Red brick = 1970 and beyond. Concrete = 2000 and beyond. These materials are only applicable to this village and perhaps the surrounding region; other areas in China have different histories.
EDIT: This answer aged like milk. For anyone wondering why this looks so different from what is on XHS/Rednote, the high effort standards of XHS combined with its generally middle-to-upper class user base leads to the very pretty—and still genuine—representations of China. The village above is mostly a case of abandonment, ergo it will be hard to develop unless if people return. This may happen, but it will take time as families make their money in the cities and then finally come back.