Earlier quoted context omitted.
I disagree. Each conference has their own goals, but I'd think that a general thread that underlies all of them is the exchange of ideas. If you can't criticize ideas ("Joe Schmoe is wrong about X"), then I'd say you're not doing a great job of exchanging ideas. I think preventing attendees from criticizing people ("Joe Schmoe is dumb") is perfectly fine, but that's clearly not what happened here.
Like I said: it's a surprising norm for a conference. But if it's clearly communicated, it's fine. It's just that kind of event. Here, it wasn't clearly communicated; if the author had seen the norm, they'd have presented something else, or not at all. What I reject is the idea that all spaces are somehow required to make space for criticism. There are spaces where that rule doesn't make sense. We're unlikely to find…
I've also seen someone asked to cover up a company T with an IMO utterly innocuous joke on it (at a different event).
But, yeah, if you want to run a conference with a CoC that basically says we'll ask you to leave if anyone is offended by you for any reason, just please let me know so I can choose not to attend.