TBF, even the article kinda disputes that moniker, but I think the intent behind it was not so much a political one... as the article says "for Barry Allen to have politics he’d actually have to have enough of a character to possess a political opinion." It's more his general attitude... he's a clean cut, square jawed CSI who is so perfect he squeeks. People give Superman a hard time for that, but he's got nothing on Barry Allen. He's a good man with no interesting characteristics in the midst of entire Leagues and Societies worth good men who have actual pathos.
But then, what makes Barry boring in the original comics is also why I still love the TV series, warts and all. In a world where Superman has to kill people to stay relevant, Barry Allen laments even the death of his childhood Bully. I have friends who won't even bother with SHIELD anymore, but who still love Flash.