I mean, I think the only issue there is that she was using a selfie stick and blocking your view of the show–that's the reason they're supposed to be banned in the first place. Whether she wants to take selfies or not isn't really anyone's business but her own. For me personally, I don't see why anyone would care how complete strangers choose to enjoy themselves on their own vacation. Like
@Goofyernmost said, the only reason people had to ask strangers to take their pictures in the 80s and 90s is because there were no more convenient alternatives, not because they were all-around better or more sociable people.
It just seems like making a mountain out of a molehill to me. On my vacations at WDW or while working there, I talk to people constantly in lines, on rides, etc. and always find that most people (including younger people) are eager to carry a conversation. If you take a selfie at Disney, it doesn't mean you never socialize with anyone ever again...it just means you took a selfie.