Yeah, that's also not what happened. The move to incorporate markets was done after substantial poverty alleviation. Markets were created specifically to address exactly what markets are good at: allocation of resources in complex fast moving supply chains. Private ownership of land is still impossible, over 50% of the economy is still directly managed by the state planning systems, every major corporation has the state planning system as a stakeholder at all times, violation of the public trust is still punishable by total liquidation up to and including the death penalty. Markets are useful. Again, no one argues that they aren't. Again, Marx detailed precisely how and why markets are useful. It's not a surprise, it's not a shock, and it's not a violation of communist theory, it's a validation of it. China is continuously in a process of active development of a society that is not ruled by capital but is instead ruled by the needs of the masses while still solving incredibly complex coordination/resource allocation problems. In the West, markets cause homelessness and food insecurity because markets are the most important thing (to the point where the imperial hegemon will literally invade your country and everyone else will support them for your crime of not using markets). Under communism, markets are less important than housing abundance and universal access to nutrition.

The expansion of marketization in underdeveloped sectors helped stableize their development, but it was not the driving factor for growth. The commanding heights of China's economy remain socially owned and largely planned, but this isn't as efficient for developing industries, which is why China expanded marketization. See GDP growth before and after Reform & Opening Up:

In short, they course-corrected to a more traditionally Marxist understanding of economics, and saw increased stability.

At some point it's like trying to make money in the stock market between 1990 and 2000. No matter how bad your plays are, you're still going to make money (industrialization, regardless of ideology). I don't even think there's much in the original meme about market economies beyond the mere mention of capitalism but one could also argue those are approaching orthogonal concepts at this point?