Your job seriously considers "women, am I right?" to be sexist talk?
Be honest, if one of the guys at work said that joke, if one of the guys, during a bit of banter, said "no women eh? At least we can finally get a bit of peace and quiet here now right guys?"
Would you seriously submit a formal complaint? Or even be offended in the first place?
The argument that Colin is a public figure is nonsense. He's some guy who works for a b-tier gaming website. He's not a celebrity, he's a no-one. Nothing he says will change the cultural zeitgeist. If he went into a bar, no-one would recognise him, if he started spouting political opinions, people would say "who gives a damn what you think?" and it wouldn't do a damn thing. His joke would never have changed a thing if people didn't jump on the outrage train.