The USSR was a socialist federation of countries, with public ownership as the principle aspect of the economy and the working classes in charge of the state.

I'm suggesting that growth is uneven, to even flatlining at periods. This is a consequence of the adoption of capitalism.

The protests and riots in Beijing in 1989 were multi-faceted. Among the protestors were hard-line Maoists that supported the older Gang of Four, while being accompanied by students that sought liberalization of the economy and an end to the rural subsidies equalizing rural and urban development. This was further agitated by western elements pushing for regime change.

It's Socialism with Chinese Characteristics, and it's still dominated by the proletariat. Public ownership is the principle aspect of China's economy, and capitalists are held on a tight leash to focus on developing the productive forces. The large firms and key industries in China are publicly owned, it's only the small and medium firms that are private.

The form of democracy and the mode of production in China ensures that there is a connection between the people and the state. Policies like the mass line are in place to ensure this direct connection remains. This is why over 90% of the Chinese population supports the government, and why they have such strong perceptions around democracy:

China does have billionaires, as you might then protest. China is in the developing stages of socialism. Between capitalism, which is characterized by private ownership being the principle aspect of the economy and the capitalists in control of the state, and communism, characterized by full collectivization of production and distribution devoid of classes, is socialism, where public ownership is principle and the working classes in control. China in particular is working its way out of the initial stages of socialism:

The reason China has billionaires is because China has private property, and the reason it has private property is because of 2 major factors: the world economy is still dominated by the US empire, and because you cannot simply abolish private property at the stroke of a pen. China tried that already. The Gang of Four tried to dogmatically force a publicly owned and planned economy when the infrastructure best suited to that hadn't been laid out by markets, and as a consequence growth was positive but highly unstable.

Why does it matter that the US Empire controls the world economy? Because as capitalism monopolizes, it is compelled to expand outward in order to fight falling rates of profit by raising absolute profits. The merging of bank and industrial capital into finance capital leads to export of capital, ie outsourcing. This process allows super-exploitation for super-profits, and is known as imperialism.

In the People's Republic of China, under Mao and later the Gang of Four, growth was overall positive but was unstable. The centrally planned economy had brought great benefits in many areas, but because the productive forces themselves were underdeveloped, economic growth wasn't steady. There began to be discussion and division in the party, until Deng Xiapoing's faction pushing for Reform and Opening Up won out, and growth was stabilized:

Deng's plan was to introduce market reforms, localized around Special Economic Zones, while maintaining full control over the principle aspects of the economy. Limited private capital would be introduced, especially by luring in foreign investors, such as the US, pivoting from more isolationist positions into one fully immersed in the global marketplace. As the small and medium firms grow into large firms, the state exerts more control and subsumes them more into the public sector. This was a gamble, but unlike what happened to the USSR, this was done in a controlled manner that ended up not undermining the socialist system overall.

China's rapidly improving productive forces and cheap labor ended up being an irresistable match for US financial capital, even though the CPC maintained full sovereignty. This is in stark contrast to how the global north traditionally acts imperialistically, because it relies on financial and millitant dominance of the global south. This is why there is a "love/hate" relationship between the US Empire and PRC, the US wants more freedom for capital movement while the CPC is maintaining dominance.

Fast-forward to today, and the benefits of the CPC's gamble are paying off. The US Empire is de-industrializing, while China is a productive super-power. The CPC has managed to maintain full control, and while there are neoliberals in China pushing for more liberalization now, the path to exerting more socialization is also open, and the economy is still socialist. It is the job of the CPC to continue building up the productive forces, while gradually winning back more of the benefits the working class enjoyed under the previous era, developing to higher and higher stages of socialism.

In doing this, China has presented itself to the global south as an alternative to the unequal exchange the global north does with the global south, which is accelerating the development of the global south. China is taking a more indirect method of undermining global imperialism than, say, the USSR, but its been remarkably effective at uplifting the global working classes, especially in China but also in the global south.

It's not about "ducks quacking" or any of that vibes-based analysis, but consistent materialist analysis.