It becomes a conversation-halter when they don't tell you what their relevant life experience is (or why it's evidence for their position). In that case they're just saying "I'm older and wiser, someday you'll understand". It may turn out to be true in some cases, but it is not reasoning.

I've had this experience a few times when arguing with my dad. Not very recently, mainly when I was a teenager. I knew little if anything about real rationality at that point, but even then it seemed very wrong to me. I was thinking (when it was too late for me to say it, o'course), "Can't you just respond to my arguments as though it were someone your age saying it?" and "If that's what you think, then why didn't you just say that at the beginning? It sounds like you're only saying it now because you can't think of an actual response." and so forth.