They could have done that without showing all the gore - the camera could have panned to the others and showed their reactions.
I don’t even like to see the zombie kills as graphic as they are, let alone main characters - which is why I don’t usually watch zombie, slasher, or other evil spawn type shows.
Of course that’s actually what they did. You didn’t see most of the hits, just heard them, they were either in reaction shots, or angled so you just saw Negan’s head. The funny part about that is that showing less actually makes the viewer see more. When you just suggest stuff the brain of the viewer inserts the details, and the brain of the viewer is usually way more brutal than any director. Really compared to things like the Terminus assault or the Governor beheading Hershel there was actually significantly less gore, but they spent a lot more time contemplating it. Usually they do something brutal and move on, since last week was all about breaking Rick they lingered over it.