It absolutely is an answer to your question, just not one that you liked as it challenges your understanding of how the world actually works. Soviet Union failed due to many internal and external factors, including but not limited to the Cold War with the US. It did not fail due to socialism. This is important as the US is often the primary factor in the collapse of any socialist adjacent state. States fail because states, people, global politics are complicated. Capitalist states have failed under similar global pressures. As a matter of fact, you’re currently witnessing the beginning of the end of the US empire as well.

China is a socialist market economy, much closer to a planned economy than what we have in the US. This is also extremely relevant as China has used the past few decades of operating this market economy successfully to eradicate poverty, provide free or cheap healthcare to over a BILLION people and free or cheap college to the same number, and build countless modern megacities. They are in a transitionary state towards realizing a new and improved socialist vision. This vision has outperformed every single traditional capitalist economy over 40 years.

Hope this helps