"RTFM" was a terrible way to talk to people. It drove people away from projects. That was one of the first things any of us realized about the way open source maintainers and their projects' communities "supported" people: by blasting them until they retreated. It was something people said to new users for little while, thinking they were being funny, until it became The stereotypically rude thing you can say to a confused user, for the rest of time.
However, there has literally never been a time when technology was supported primarily by documentation. Not during the computer age, not before the computer age. People teach other people how to use things, it's how it's always worked and how we've always learned best. It's why schools exist.
I am by no means anti-documentation. I enjoy writing documentation; here's a screenshot of my homelab's documentation folder if you need proof.
But it's important to recognize that I write these things because I might need to look something up quickly as a reference, not because I expect anyone else to learn how to maintain (let alone build) my system by following the docs.
Reference manuals and tutorials are important to hook people into a project and support their use of it. Books are written to cover popular projects for people who, unlike myself, actually do prefer reading it all and have the patience for that. I just don't want us all to pretend that there's some moral failing if we haven't read the entire textbook before we ask a single question.