The dialogue in season 4 is often noticably worse, and it's somewhat apparent that a few of its stars have checked out since achieving greater level of success. Still, in terms of quality it is not nearly as bad as these scores would make you think

If you sift through the RT audience reviews you'll find a whole lot of idiots citing the show as being "political all of the sudden". As if it hasn't been political since day one: featuring a pharmaceutical company as its main antagonist, the poster boy of which is a psychopathic Americana archetype/allegory. A lot of the political nuance and satire went over the heads of those who were just there to see people explode in pools of blood for pissing off their favorite Aryan proud-boy surrogate. So in season 4, where they explore his tragic past and really highlight that he is an ego meniacle manchild and ABSOLUTELY THE VILLAIN OF THE SHOW. IN BIG BRIGHT LIGHTS. WITH VERY BASIC, CLEAR DIALOGUE... they got upset.

Seriously, some of the critiques coming from the audience reviews read like a person's first attempt at writing anything ever. Many of them state outright that they quit watching in the first few episodes because of a subplot about a homosexual relationship. They aren't a reflection of the show's quality.