I would love to get some examples on how "life experience" in general is necessary for an informed and rational opinion on a subject. The examples in these comments seem to relate to not "life experience" but specific experience (i.e. doing tracings, playing chess, etc.) Yet people seem to think that "life experience" in general adds "something" and that further conversation on the subject cannot substitute for it.
As someone whose peer group is generally much older than me, I can say from comparing myself to others that "life experience" doesn't add to your knowlege or intelligence or mental development, past a certain age. What it does add is context. As you get older, your context shifts--certain things that you thought were important no longer are important and certain things become more important. I think it's explaining this context shift that is so difficult (but not impossible!)
For instance, my younger self had serious worries about her relationship that now seem trivial. This is because I've learned that communication and trust are much more important to having a healthy relationship than physically being close to someone. And this context shift comes from simply life experiences in dealing with people.