I hardly see what makes him a bully, but both sides have some fair points. So all in all, it's fair game. Of course it sucks to be on the losing side (as Ingraham is in this case), but that's reality for you. I'm sure if a large group of people contacted those advertisers in support of Ingraham, that could change the outcome, but that wasn't the case.
You don't see how using social power to hurt someone professionally for a minor offense makes one a bully?
I also have my doubts that the people who backed Hogg outnumbered those backing Ingraham. Companies that insert themselves into these spats without good cause (O'Reilly being an example of good cause) tend to do themselves damage by taking sides. See Dicks having trouble after they changed their gun policy.
But that's neither here nor there. The question is to each person. Simply looking at something and saying that a person was in the right because they "won" is silly. Bullies win socially all the time. You'd basically be justifying every mean girl who ever lived who mentally and socially tortured someone because of a perceived slight or threat. As adults we shouldn't be handing such power to a high school student and when they use such power, we should be condemning him and all around him.
I never said anyone was right because they won. Not sure where you're getting that from. I said both sides had fair points and that it was fair game, though Ingraham felt the most impact. Ingraham clearly went looking for a conflict, but she just didn't expect to lose. That does not at all equate to sanctioning bullying and mental and social torture.
He provided an avenue (calling her sponsors) for people that disliked her course of action (making an unprovoked personal attack against a 17 year old mass-shooting survivor, which is bound to attract negative public attention, because when you think about it, that's a pretty twisted thing to do) to make their voices heard. It seems to me like she hurt herself professionally.
To me it's irrelevant wether he's a high school student or not. His actions should be judged based on their own merits, not based on how old he is, and I don't see anything wrong with his actions in this case.