As it happens, I somewhat agree with you that if it's clear someone is asking a question about physical self-defense, answering by referring to other kinds of self-defense is kind of changing the subject.
But some people don't agree with you about that distinction. And a great many more are perfectly happy to change the subject a little bit, to expand it in ways that many people find interesting.
So I'm not sure what you're really asking with this thread. No one's going to suddenly say "you know what, you were right all along; I just didn't see it until you explained it one more time."
. Because as far as I can tell it's not that they don't understand you; they either disagree or don't care.