There's literally nothing inherent to a socialist system that makes a society less racist. You are giving the majority more power over vulnerable groups though. You can say that sounds like I'm defending the rich but I never said that. Sure we can learn from it. We can eliminate majority power over capital control. The CCP argued that the USSR had strayed from the true intent of Lenin's Communism. It got them famine and they reverted. Yes, Lenin argued that it was more an approach than a set system. The issue with that is what the proposed approach is inherently oppressive. Lenin himself argued that dissent could not be allowed to exist because it would undermine the system.
Your argument that we can at least try ignores consequences that we've seen before. We also could try an ethnostate. That would provide the unity required. Those pesky minorities keep getting in the way of progress. How dare they want to keep the value of their labor. We could try shooting ourselves in the foot through radical change to try an experiment that could just as easily be formed internal to the system.
There's nothing stopping left systems for existing within western societies. The corporate structure actually allows for it depending on how you write the founding documents. Co-ops succeed all the time and they fail all the time. Nonprofits do a lot of the same. When these systems are not at a government level, when the trust fails and the system collapses it does not take everything down with it.
It's really difficult for a government system supporting capitalism to break down because it doesn't provide anything inherently required to live. In a command economy, when the trust is broken, the system breaks down. When the system breaks down, the people go to other systems for their needs. Then start the power struggles and the death. It's authoritarian and unstable by it's very nature and it has a tendency to become more authoritarian and consolidated as time goes on due to lessons learned.
Why would you knowingly choose this path when reform and regulations are an option? What is different about your approach from China or the USSR other than you'll just attempt it better or be more forceful in pushing your ideal code of ethics?