Feasible? Only in smallish communities surrounded by arable land. The urban and suburban life needs large scale industry to function at all.

Contradictory? Not at all. Radical just means opposed to the status quo, “leftist” is pretty broad but is generally used to mean “left of the DNC” by politically engaged people and “left of Ronald Reagan” by MAGA. Marxism is a specific foundational political philosophy that identifies and idealizes a communist society.

Just because the monkeys on typewriters don’t know the definitions doesn’t mean the words don’t go together.

They haven’t thought that far ahead.