I would agree with this. Ten or fifteen years ago, Savage was just a writer who had a semi-satirical advice column in local weekly papers. Nowadays he's been positioned as a kind of pundit for LGBT people (but gay men especially) and that puts what he says under up to more scrutiny. I don't think glitterbombing him is an effective form of protest or discourse, but I think a lot of the criticisms levied against him are valid.
Sort of on that point, Lindy West, who writes for Savage's paper The Stranger, actually wrote a pretty scathing response to him about how he talks about fat women in his column. Ultimately, the point she raises applies to all the shitty stuff he says to people in his column: if you're trying to change things for people, then he needs to change some of his own attitude first.
http://slog.thestranger.com/slog/archives/2011/02/11/hello-i-am-fat