What in the hell does this even mean? We already have social security, food stamps, tax transfers, public services for the homeless, medicare and medicaid. How is this new system going to be qualitatively and not just by degrees a different type of economy that is not "capitalist" compared to what we have now?
Is not not going to have banks? No, it will have banks.
Is it not going to have capital markets? No, it will have capital markets.
Is it not going to have the private ownership of assets? No, it will have the private ownership of assets.
Is it not going to use currency as a medium of exchange. No, it will use currency as a medium of exchange.
Is it going to use the government to redistribute wealth? Yes, just like we already do.
That is simultaneously socialistic and capitalistic just like almost every country in the entire world is.
This guy is partisan policy pandering and framing it as a revolution. I think he is decorated or respected in certain economics circles or whatever but when you evaluate his words he clearly fails to understand basic concepts of his field. He's a hack.
He has also failed in a practical manner. His time as Greek Finance minister was short but spectacular.