Communism, communist, anarchists, etc. have a lot of variety and internal difference. It's hard to generalize them all. For example, on state power, Marx was early on a journalist and had seen first hand how the violence of the state can impede speech when it raided their presses. He was well aware of the inherent violence of the state. Communist activists have also historically also been victimized by the state.

Also Communism is generally seen as a stateless society once class antagonisms have been withered away. I'm pretty sure you have Engels saying the state should 'wither away'

I don't find it surprising that there'd be some overlap and agreement on some issues with libertarians for instance, a group also containing differences.

Obviously all this doesn't negate there are different viewpoints how to get to a stateless society.