JBL. Automatically a lot of people shoot towards Otunga and Saxton and yeah, they are bad. They are boring. But they also aren't dominant voices in the commentary. It's often easy to just block them out and forget they are there.
JBL, on the other hand, is always noticeable. And he has to constantly yell at and try to intimidate the other commentators in order to come across as a heel commentator and I feel that is ridiculous. Jesse Ventura raised his voice occasionally and so did Bobby Heenan, but both guys were able to get their point across without yelling all the time. JBL seems like he is trying to intimidate his fellow commentators and that has never sat well with me.
Furthermore, JBL seems to sometimes forget he is a heel commentator. He'll praise legends and then a sentence later condemn them. I'll never forget Survivor Series 2014 when Sting showed up and JBL seemed excited and happily listed off Sting's accomplishments. Then, he berated Sting for having no business being at the show... although a few seconds later, he was excited about it. And he does this A LOT.
But mostly it's the yelling at the other commentators. I can ignore Saxton and Otunga when they are annoying. I can't ignore JBL when he is annoying.