I don't think that's true. For example, the recent changes to the Ruby code of conduct removed the parts about assuming good intentions. On the other hand, the guidelines:
> When disagreeing, please reply to the argument instead of calling names. "That is idiotic; 1 + 1 is 2, not 3" can be shortened to "1 + 1 is 2, not 3."
> Please respond to the strongest plausible interpretation of what someone says, not a weaker one that's easier to criticize. Assume good faith.
> Please don't use Hacker News for political or ideological battle. It tramples curiosity.
HN ideology is basically "we're all adults here, act like one". People that push for stuff like code of conducts usually consider that these guidelines are not enough to protect marginalized people. So they add stricter rules about how to act. That means that you have to agree with them about who is marginalized, that they need protection and how to protect them. I don't think any of this is universal. Note that I don't mean that this is a good or a bad thing, just that it's politically charged in some way. That's nothing new, since free software has always been politically charged. But the values conveyed by code of conducts are not always the same as the "old values of free software/open source". This is of course very vague, because everyone has their own values and most projects aren't very clear about what their values are. But you can see the consequences of that change when you see how the opinion on Richard Stallman changed, or how Linus evolved. Again, I'm not saying any of this is good or bad. I'm saying that things are changing and not everyone agrees with it.
Now on the American-centric part. I don't think I can add anything worthwhile to what's already in this article: http://antirez.com/news/122.
They generally have a strictly US-history based view of how to treat other people and deal with their insecurities and problems. They're also invariably passive-aggressive and just plain hostile in places.
When you are in a stage of pulling CoC rules out, you are already nuclear and hostility is already ongoing.
They are US based, yes, but they are usually good rules. Whether a CoC is bad or good is in the hands of the humans enforcing it. The .NET Foundation shows terrible human to human handling of a non CoC related topic.
A CoC is always toxic, because it is the flag of a moderating team that is not adult enough to recognise that you can tell someone "no" without having some sort of "legal body" to point to.
More importantly, a CoC is a commitment by the moderation team to follow a certain standard, instead of giving it a position of "whatever we say is right, if we don't act, sucks to be you". (And at the same time, it's just that, a commitment, it can still be ignored or misused, it's not an automatic fix for anything)
A CoC is an admission that whoever moderates the community is not capable of doing so without having something to hide behind and point at. Culture is not improved by introducing rules-lawyering and avoiding personal responsibility, that is how you ruin it.
Edit: What good does a commitment do anyway, if it guarantees nothing and changes nothing? It's just someone shouting, hoping someone else hears and approves. If anything, that underlines my point about the fundamental immaturity of the decision to introduce a CoC.
Edit2: I understood your point to be that introducing a CoC means a commitment, which is somehow something that is good. When all this commitment does is deflect responsibility, that is not a healthy result. I feel like that addresses your point fine.
A CoC doesn't automatically deflect responsibility. As a moderator you still need to actually moderate, and you get the feedback for doing so. As a commitment, it actually puts an extra burden on the moderator, since there's now an explicit thing people can point to when criticizing your (in-)actions.
I happen to have gained a moderator role in a community that has a pre-existing CoC. I'm not sure why I would "hide behind" or "point at" the CoC when acting in that role, I'm perfectly fine with telling people off (or more if necessary) without doing so.
And yes, if you assume the worst of everybody commitments don't have any value. But people generally attempt to actually uphold things they commit to, and thus it is seen as a positive signal, even if it's not a guarantee. (Ideally we wouldn't need CoCs because the baseline established by them would be such a universal commitment in society that you could just assume it to be valid everywhere, but experience shows that's apparently not the case) Several community members told me that it has been relevant to their decision to interact/join.
EDIT: and even if you say just a commitment is worth anything (as said above, I personally also don't think "has a CoC" is that much of a signal without seeing how mods actually act, but clearly other people do), that's quite a difference from a blanket "CoCs are always toxic".
