Did you read the first post on the thread? The one that described the situation that resulted in the vote-kick?
Every single word.
If someone thinks that there is tension in the group and wants to have a chill and relaxed time, saying hello and striking up conversation helps change the pace of the flashpoint. OP didn't do that, from what I can infer. Furthermore, the attitude of his post sucked and I would assess that his attitude during the FP sucked as well.
Pulling random mobs and killing the group is borderline unacceptable: aggro range doesn't change just because you are in a flashpoint, look around and use common sense.
Being that he was new and wanted to watch every single conversation, he should have stated that to the rest of the group from the get-go. I would never kick someone for being honest about that, but I might leave and spend my time better elsewhere.
I suspect that his group kicked him not only for wasting their time, being undergeared, pulling random mobs and getting them killed...but also for not communicating their needs to the group. He also stated that he has been kicked multiple times (every HM flashpoint he has been in, I believe) so its hard to believe every single one of those groups were just elitist.
The best part of his entire post is that people's actions in SWTOR are making him give up his hope for humanity. I LOL'd.