China dominated the Top500 list by 2017, with 202 machines compared to 143 from the U.S. Then the U.S. restricted Chinese access to Intel processors and other U.S. hardware in 2015, followed by broader export restrictions under the Trump administration in 2019, which have been tightened further by the Biden administration in 2022. As a result, Chinese participation in the Top500 list dwindled, to some degree because access of Chinese entities to the latest hardware got harder and to some degree because Chinese scientists no longer want to share details about their machines with anyone.

Why is anyone surprised that the country with the highest research output, that has historically dominated the Top500 list, has the fastest supercomputers?