Is nationalism going to peter out? No, of course not. Do some people care for reasons that are important to them? Sure, I don't want to tell anyone how to feel. I am just another jerk with an opinion like the rest of us.
But if you were to ask me, it's take it or leave it. I'd be more than happy to see free movement in the world. Just another set of rules I'm not using.
But: back then only a handful of very rich people had the means to do that, and taxation and social protection were much lower than today. Those things are related. They (IMO of course!) are what make borders a pragmatic necessity.
Maybe you can afford Universal Health Care after all...