In my experience, CoC's are never a problem, and are even welcome by those who naturally stay within their guidelines.
NEVER a problem? Did nobody notice the huge scandal when a CoC for Linux was introduced which resulted in Linus Torvalds leaving the project and several other Linux contributors threatening to revoke the licenses for their contributions, which could have resulted in the destruction of the Linux project in total and in the destruction of 90% or whatever of computing infrastructure, since most computers run some kind of Linux.
So just recently a useless CoC almost destroyed most of the computing world, but you don't see a problem in that, if everyone just pretends to be nice to each other.
1. Perhaps you
have to pretend to be nice to others. I don't have that problem. I suspect most people don't have that problem. At minimum, folks can be civil with one another, or just not communicate at all when even civility isn't possible.
2. The Linux situation was a very different deal, with entirely different circumstances and implications. You're conflating two very different things. I suspect you knew that when you wrote it. And anyway, the sky didn't fall. A new CoC didn't bring the Linux world crashing down. Your example kinda defeats itself. Hypotheticals and "what-ifs" don't make compelling arguments.
It's weird that you're even acting like a COC is some bizarre or unprecedented thing. The vast majority of message forums and online communities require you to accept a CoC before you can even sign up. Some require you to click "I Accept" every time you log in. Some keep it pinned at the top of their forums for easy reference when issues arise. Believe it or not, those communities do just fine. It's unusual for a forum *not* have a CoC than *to* have one. These forums, 'til now, have been the exception, not the rule.
Your histrionics and doom-saying are completely unfounded and, really, kinda silly.
So, yes. I 100% stand behind my statement that in my experience, CoC's aren't a problem for people who naturally stay within them without needing to be reminded. They're only a problem for those who can't, or don't want to. For most everyone on these forums, nothing is going to change. They'll continue posting as they always have.