Only because the very concepts of ownership and the collective-individual dichotomy are necessarily vague and subjective. China considers themselves socialist because they equivocate the people with the state. If the people are collectively represented by the state and the state owns (some of) the means of production, then at least transitively the people own (some of) the means of production.

As an anarchist I don’t believe the state adequately represents the interests of the people, nor do I think it could even if it were radically democratic and egalitarian, though I would still certainly prefer that to the existing status quo. Somewhere a line must be drawn arbitrarily and I prefer to draw it on the other side of authoritarian state control.

• https://press.un.org/en/2019/sgsm19779.doc.htm
  Helping 800 Million People Escape Poverty Was Greatest Such Effort in History, Says Secretary-General, on Seventieth Anniversary of China’s Founding
• https://www.worldbank.org/en/news/press-release/2022/04/01/lifting-800-million-people-out-of-poverty-new-report-looks-at-lessons-from-china-s-experience
  Lifting 800 Million People Out of Poverty – New Report Looks at Lessons from China’s Experience

Do you take the Chinese citizens at theirs?

We find that first, since the start of the survey in 2003, Chinese citizen satisfaction with government has increased virtually across the board. From the impact of broad national policies to the conduct of local town officials, Chinese citizens rate the government as more capable and effective than ever before. Interestingly, more marginalized groups in poorer, inland regions are actually comparatively more likely to report increases in satisfaction. Second, the attitudes of Chinese citizens appear to respond (both positively and negatively) to real changes in their material well-being, which suggests that support could be undermined by the twin challenges of declining economic growth and a deteriorating natural environment.

Very few governments on this planet have approval numbers this good, and even fewer have numbers this good when it’s a neutral third party conducting the surveys.

You could say the same about every developed nation

“Developed nation” is a propaganda term designed to make you think that the overexploited nations of the world are on some mythical path that will lead them to a first world quality of life.

every western European country has already eliminated the worst kind of poverty and on average European citizens are better off than Chinese citizens

This is an apples-to-oranges comparison. Europe is the beneficiary of hundreds of years of imperialism and accumulation and the ongoing system of global unequal exchange, whereas China is a former victim of said imperialism that has pulled themselves out of the muck with their own workers’ labor. China is better off compared to India, which achieved independence not long afterward but has fallen far behind in every single development index because of their failure to overthrow capital.