“But it was superior then.”
Then was a loooong time ago.
And the bad software well predates the communist takeover.
Four thousand years of Chinese superiority was a long time. Britain's several century long period of ascendancy is short compared to that. Good vs bad software is relative. China used to have superior software, then fell behind. Without the 30-year interlude of Marxist economic planning from 1949 to 1979, China would already have the biggest economy in the world, by far (50%), if you use Taiwan's (the laggard among ethnic Chinese-run, majority ethnic Chinese economies) GDP per capita. If you use Singapore's per capita GDP, then China's economy would be 4x the size of the US economy. We are fortunate that China went through its communist interlude - it slowed them down. China is an ancient empire that has traditionally expanded its territory in times of strength. We will be grateful for that respite in the decades ahead.
Perhaps in prehistory, during a time no one remembers. Chinese thinkers of 2300 years ago do not compare favorably against the Greeks of that time.