Media criticism is welcome here, so long as everyone is respectful. Art is inherently subjective - people are going to like different things for different reasons, and it's okay to say you didn't enjoy something.
I'd discourage low effort discussion though. Instead of saying "Voyager sucks" let's try "Voyager didn't work for me because it was too episodic" (not a criticism I personally have, just an example).
I'd suggest reviewing the posting guidelines in the sidebar, and if anyone gets nasty or you see harassment feel free to file a report or shoot me a DM.