some ppl feel good about insulting others I guess, I agree, it's not nice and doesn't carry much weight so I tend to ignore those ppmpous a~holes because they aren't worth my time...be yourself ~ if they mind they don't matter, if they matter they don't mind. (dr.suesse)
I think, it's mostly used when someone did something naive and it backfired. The speaker wants to point out, that he knew this would happen.
It;s a pompous thing to say in the first place, but I don't think it means an experience is more legitimate than another, it's whether a person's understanding and interpretation of the world is realistic
that's right! who's to say, who's to say?