You misread my comment rather heavily there. Codes of conduct are (one part of) a solution to a very real problem. There's no problem to be solved with "protecting 'political opinions' that hurt people", and even if there were it'd be far lower priority than people's lives.
And to answer your first sentence: people have learned to couch their intolerance in less blatant ways, but that doesn't make them less of an attack on other people's rights. People regularly think, incorrectly, that their discomfort is more important than other people's lives and rights. People push back, point-by-point, on each individual right or ability to exist and thrive in society. And most commonly (though not always), the people saying such things already have their own rights respected.
> Should people not be able to feel comfortable discussing such opinions outside of work or project spaces?
No, they most certainly should not. They should feel about as "comfortable" as people slinging around slurs and advocating segregation. That's nearly unthinkable today; there was a time when it wasn't. People's comfort "discussing" such things comes directly at the cost of the people they're hurting or advocating against. (And in any case, don't overestimate the weight due your opinion if you're not part of the group in question.)
Nobody is being run out of a project over the slightest misstep; the first response to most issues will be communication, not bans. Bans from a project are the last resort, not the first. People who work in projects with codes of conduct don't go around afraid they're going to be booted.
Beyond that: what work do you need to do that you can't possibly accomplish without hurting people? It's really not hard.
In that case "be excellent to each other" should be more than enough.
"Explicit guidelines have demonstrated success in other projects and other areas of the kernel."
Many people do not start out sharing a common understanding on this topic. This HN thread is more than enough evidence for that. Hence writing down a framework to give people that common understanding.
Should people not be able to feel comfortable discussing such opinions outside of work or project spaces? I'd also like to point out that being against gay marriage is extremely common among devotes of the Abrahamic religions, which is a category that appears in the "protected list".
Opinions such as those have already been used to try to oust (not sure how it turned out) a member of at least one open source project (Opalgate, no CoC needed ironically) speaking entirely unrelated to the project. He was not directly maligning anyone from the project itself, in fact an outsider had to come in to stir drama (and that outsider happened to be the author of the Contributor Covenant. Hmm...).
What people do on their own time that does not personally affect you is their own business. Remember that principle is how gay rights came to be accepted in the first place. And no I don't need a link to the Paradox of Tolerance.
> I seriously doubt you'd find anyone's role in a project at risk because of their thoughts on climate change.
I would not be so sure. As before, often any skepticism of prevailing climate change wisdom is instantly escalated to "science denial". Not a good label to have in a tech project, and besides you'd be advocating for "crippling temperature rises, mass natural disasters, entire cities wiped away by see-level rises, destroying the planet basically". That sounds kinda life changing, if you believe it.
> Not particularly long nor hard, no; I run into them regularly.
Would be really interested to see some examples of this. Not just random twitter twattery, but people actually involved in OSS projects, literally advocating genocide.
> Even leaving aside whether there's any problem here at all, since when have the choices been "perfect solution or no solution"?
Well you said it yourself, there's no problem, thus no need for a solution. The Contributor Covenant is a solution in search of a problem. Are there any examples of the Linux kernel project being bogged down by external social politics (not that this CoC would fix that, much the opposite), or excessive trolling? Far as I can tell the problem was Linus's own abrasive attitude.
And let me tell you, he's hardly alone with that attribute. There's plenty of people out there who are difficult to work with because they are full of themselves and have little tolerance for dissent. At least Linus was upfront about this, rather then preferring to feign politeness then stab you in the back via bureaucratic bullshit, kinda like this CoC encourages.