[dude with glasses in a communist t-shirt, arguing] I'm the only leftist here, your opinions are TRASH
[dude holding a theory book on smug, arguing] Read theory you losers, you're all WRONG
[dude in an anarchist hoodie, arguing] Nuh-uh, I'm the only leftist here, you're SHITLIBS
[the three dudes are now caught in a cartoon fight, glasses gone flying, punches everywhere, while a firing squad of nazis are targeting them with rifles]
[a confused nazi asks] Why… why are they still arguing?
Trying to decouple the term and core ideas from the past actions is going to be an uphill battle forever. That requires imagination and forward thinking, but you have the folks dunking on it because of the atrocities carried out under it, and the folks on the other side that have managed to embrace those parts so hard that they can no longer sea reason or find nuance.
Yes it is exactly like how antichrists have co-opted the term Christian. For many if it ever was, it will never be clean again in their lifetime unless there's some massive Purge. They never were Christians and, will never be christians. But as long as they're allowed to be the face of Christianity it's only going to hurt it as a whole. At least more than it already hurts itself.
Yes, we need a "brand" that builds upon the ideals (and some of the theory) of communism/Marxism while taking in account both history (e.g. even something as simple as democratic governance being non-negotiable) and the "spirit" and challenges of our times.