This topic is acting pretty predictable - Most posters already disliked PewDie to begin with, and therefore don't watch his videos for an impression. My first reaction is this is fake in some way, such as a stolen login due to his popularity. My second reaction was that the video is a clear insult against him. Not that at this point he shouldn't be jaded to hate, but this is a popular video centralized around hating on him for how he is passively. Sure, he has come to catchphrase himself and such, but in his mind it is passive and what makes him him. Yes, he yells. Yes, it can be annoying to some people. But you're picking out how he is and hating on him for it. He is a human being like anyone else, and such centralized hate on how you act having fun, doing your job, is hurtful.
That is not to say, real or not, it isn't bad to say. He should have kept his mouth shut, sure. But give some understanding.
At first i liked Pewdiepies videos. I thought he was funny. The more videos i watched the more apparent it became that he was only acting. I already hated his fans.
the more apparent it became that certain ways he acts during his videos, people loved and repeated, and as such he would amend them into his normal gameplay.*
People liked how he acted, and then he would see everyone commenting these lines and it'd make him passively repeat it more. Imagine if you had a low tolerance for scares permanently, and as such you'd freak out. And you make videos, become famous, people repeat certain ways you freak out. People enjoy that, and for you it is how you are, so you just start using it as an escape...