In my personal experience such statements are actually not rare among specific minorities, and only in spaces between those minorities. They will never be said in a public way, because it makes them targets. I've been pulled aside by fellow minorities and warned against communities I had expressed interest in in the past, always in private in confidential spaces.

I openly advise my students to stay away from posting questions on StackOverflow and ask for help among their peers and teachers. At least until they're able to clearly grasp what the "Minimal Complete Verifiable Example" is, how to minimize code, and how to google problems with slight variations, which are not easy skills.

It's not to say that StackOverflow is generally toxic. It is, though, unusable by beginners, and it's mostly by design. And I don't think there is a good way to communicate this to a beginner whose question has been just closed because it lacks details.

Oh, I think they are not as rare as you think. People are actively deterred from, say, Linux kernel development because of the community.

have you seen a thread discussing OCaml recently?

OpenBSD

Have you ever tried learning PHP? Even the people that don’t actively work with it are toxic :P