I think Robert can be tempted to try newer music. At least that is if he wants to. But sofar I have seen him being openminded, so do not lose heart tuohey :)
I think some things are just taste based, and I am fine with that. Again: people shouldn't expose themselves just for its own sake. But neither should they limit themselves. I mean, have you lost any curiosity at all? If you like macaroni, that doesn't mean you'll eat macaroni your entire life, does it? I think in these kinds of debates one need to appeal to that curiosity, and not argue all too offensive (I wont say "that may be just about the saddest thing I have ever read", but I don't judge ;) )
I wonder, (but maybe we should start a post 1913 appreciation class, to gradually expose people, at least that worked for me), I wonder, what is the most out of the box music you actually liked, and why? Then try too expand on that, give something slighlye furter out your comfort zone a few listens. And gradually it starts to make sense, and there is no shame in slowly appreciating things :D