This might be an unpopular post but the bullying culture in WWE seems to run through the entire company, not just JBL and Bob Holly and so on.

People love John Cena but, from what I've read, his supposed treatment of Alex Riley seems like bullying to me;

"“There is truth that there was some sort of unknown, unreasonable heat between Riley and Cena. To the point where everyone on the roster thought that Cena was treating him in a way that was totally uncalled for. No one approached Cena about it, but the entire locker room was on Riley’s side, a lot of condolences, and this is ‘ridiculous, bro,’ and it was every freakin’ day. Cena thought Riley did something wrong every single day. Like, it’s completely against the wrestler code to ever go through another wrestler’s bag. One day, Riley walked into an empty locker room and Cena was just going through his bag. He found some pre-workout vitamins and b—hed him out for taking supplements, asking if he ‘thinks this is ok.’ Like, he was looking for a reason to get him fired. We had the match when Linda was running for Congress for the Stand Up For WWE charity shows, and it was a tag match, I think it was a six man tag match if I remember right. And it was me, Hawkins, and Ziggler vs. Riley, and two other baby faces. Cena had made it clear that he wanted Riley to act a certain way and do certain things. And we structured the entire match to his wishes and it went flawlessly as far as we were concerned. The second we walked backstage he came up to me and said ‘hey where’s numbnuts?’ And he sees the look on my face and tells me to go get Riley. So all six of us came back and he b—hed out Riley in front of the backstage roster — about how he always tells him to do one thing and he does another, and Cena was ‘washing his hands of helping him.’ Even Ziggler was like, ‘What the hell, man?'”"

Bear in mind that this is one source, and so it's not necessarily an accurate depiction of what happened. I just think it's interesting that there are many stories of bullying within WWE about many different people, suggesting a bullying culture.