So, in the mid-1900's there was this thing called Communism. It was a real thing, practiced in many different countries self-consciously. One of the tenants of Communism as it was practiced was that capitalism was bad, and one of the things that Communist countries did was to release anti-capitalist propaganda. So when today we talk about communist anti-capitalist rhetoric, we're not calling all anti-capitalist rhetoric communist, but rather referring to that particular subset of anti-capitalist rhetoric which was, indeed, communist.

This does not mean that such arguments are not straw manning the issue. However, it does mean that they're more nuanced than whatever the argument is that you're trying to debate with above.