I don't know what any of those individuals believe or don't believe. Unlike BLM, there is no organizational structure or group of agreed upon ideas. My guess is there is wide range of beliefs of people who identify as Antifa.
It seems there has been at least one college professor who has researched them throroughly and he refers to the ARA groups of the 80s as the pre-cursor to the American version of Antifa, not the 1920s German communists that you think they represent. My guess is you've done more research on the 1920s German communists than any 99% of the members Antifa in 2020. That said, I'm sure there are some communists in their ranks. My guess is most are anarchists based on their behavior.