The word "zombie" is more of a catch-all term rather than a technical term. We've had this discussion many times over the years and sometimes it is about what the creatures in 7 Days to Die should or should not be able to do or what properties they should or should not have given that that they are called "zombies", and sometimes it is about what the creatures in 7 Days to Die should be called (other than zombies) given their apparent characteristics. It all boils down to people erroneously thinking that "zombie" is a technical term and means something specific when, in fact, it is a general and abstract term that captures a wide range of characteristics. People who want to think narrowly about the definition of "zombie" aren't going to like that but they do have to deal with it because the developers of this game have a very liberal and loose view and definitely use the term "zombie" as a catch-all and will continue to do so no matter what abilities and characteristics they decide to give them.
So just put away your comic book/ movie/ and literary references and come up with your own sci-fi/fantasy explanations for how things work for these THINGS that everyone refers to as zombies.