And they aren't wrong, as even major China scholars like Yasheng Huang and Yuhua Wang point out that the Imperial Civil Service in China was stacked against merit due to structural issues that biased in favor of incumbents.
That said, similar issues continue to persist in China to this day due to the Zhongkao.
Specifically, if you didn't attend a academic high school (which only accepts around 45-55% of Zhongkao takers) you wouldn't be prepared for the Gaokao unless it was out of pocket at a cram school (which are now technically banned, but were anyhow exorbitantly expensive in a country where the median household income is $4,000). And if you couldn't pass the Gaokao, you couldn't attend university.
Furthermore, Academic High Schools tend to be few and far between, yet take the lion's share of resources unlike Vocational High Schools which most Chinese attend - but not the ones you meet in an air conditioned office unless you order from Meituan. In the vocational schools you see similar issues of teacher absence and lack of pedagogy.
The failure of the VET system in China has been a major sticking point in Chinese policymaking recently and a lot of domestic research is being done to understand why it failed [0][1][2]
[0] - https://www.emerald.com/insight/content/doi/10.1108/ET-09-20...
[1] - https://www.ewadirect.com/proceedings/lnep/article/view/9075