Torture is a uniquely good tool in thought experiments, when you need something bad, and I refuse to give it up.

Death is too complicated (and therefore invites too much hypothetical-fighting). There're questions of what quality of life you're missing, how long you would have lived, etc, and worse yet, some people think it's a good thing. No one* thinks torture (of the average person) is a good thing. When people say things like "I want to go on living no matter what my life is like" the only correct answer is extremely unpleasant experiences, which are also called torture. I could wrap the idea of torture in a bunch of sterile-sounding abstractions, but no one likes obfuscation, and it would still be torture. If leaving out the word "torture" changes their reaction, then including it is necessary to make my point. Anything else equivalently bad that could do the job in my thought experiment would probably be some more specific thing than torture, or disturb people as much as torture anyway.

(*Colloquial sense of "no one")

When I need to make an argument about factory farming, and I want to draw an accurate analogy, I need to bring up torture, because that is an accurate description of what actually happens in factory farms. It's not just the death in them that bothers me. Indeed, to counter the Robin Hanson argument that meat is moral, references to actual torture are the only answer (linked to cache version because as of writing this the page is down).

When I am arguing with a theist, and I need to sidestep their cached thought that people in Hell deserve it, I have to use the word torture, because that is a boo-light, and i am fully justified in using it because torture is what we're talking about.

If you can't discuss these things with me, that is too bad. Children likely have valuable insights that adult conversions are missing due to their absence, but I am still gonna talk about these things. So if you must leave the room while the grown-ups are talking, then go. Grown-ups' conversations are important, and making everything kid-friendly is not an improvement (This is also my response to the entire essay that started this thread).

I have always seen LessWrong as a place for grown-ups. An almost-grown-up can gain a lot by jumping into the grown-ups' conversation instead of talking with kids, but the real grown-ups still need to talk about real grown-up things.

As for your fashionable signaling hypothesis for jarring and vivid examples, as Lumifer pointed out, you just did it yourself. Were you signaling then? I bet not; I bet you forgot that "meat" is a disturbing mind-killer to some people, and when the idea popped into your mind, you thought "that feels like it makes my point well, and sounds kind of amusing," so you wrote it. If I told you to watch your thought experiments and examples and not bring up meat because it might drive people off, you would probably think (and be right) that that is too much effort on behalf of too small a population, if people were socially expected to watch what they said all the time like that it would make posting less enjoyable. The feeling of being made to act in a kid-friendly way is not a good one.

I don't like being around literal kids because (among other things) people expect me not to swear around them (Also partly because people expect me to not tell them that Santa isn't real, etc). And not being able to swear is frustrating. This is the same feeling that the policy you're advocating will impose on the rest of LessWrong who are not psychologically scarred.

I expect you're thinking, "Yeah, but like I said, there are lots of potential mindkillers, and lots more than a small minority are mindkilled by at least some of them. It doesn't have to be the same mindkiller that kills every mind." But either handling your personal mindkillers, or at least just quietly sitting out and not making a fuss while other people talk about them is the price you pay for sitting at the grown-ups table, and in return you don't have to be super-careful about stepping on everyone else's toes.

By the way I didn't downvote you.