obviously they've both been pretty bad, but at least communism is only bad in practice and not in theory when you're saying it out loud. it's just naive, like any genuine attempt at making a political or economic system. the national socialist party literally advocated for prejudice and enacted genocide and oppression as landmark public policy. not as an unfortunate side effect or little bump in the road, it was literally one of their goals. maybe attempts at forming a communist system have ended up badly, but at least that's not on the tin, it's just because the ideals are too out-of-reach for large collections of actual people