HN threads are supposed to be conversations. In conversation one doesn't take a recording of what one said in a previous conversation and replay it. One makes a fresh statement of one's views, even if they're mostly the same as what one has thought in the past. That's part of how we relate to each other.

https://hn.algolia.com/?dateRange=all&page=0&prefix=true&que...

Submissions and comments play different roles. Submissions provide topics for conversation. Once enough time has gone by—on HN, about a year—the cache is considered clear and the floor is open for a fresh conversation on that topic. https://news.ycombinator.com/newsfaq.html

> Please don't teach people how to self-censor.

You could say that about any rule that asks users to do one thing rather than another. I think most people here would support "please don't copy/paste into the threads" as serving the overall quality of the forum rather than seeing it as a censorship issue. This is the sort of case where it's probably good to have a rule, since the thing we want to avoid is having copy/pasting become common.

https://hn.algolia.com/?dateRange=all&page=0&prefix=true&que...