It's a funny line but I usually find that silly. I don't think our music will ever be called "classical" music because "classical" doesn't mean "old" or in general music that's stood the test of time. It's a term specifically used for the classical period mostly associated with Vienna. It's not just a specific type of music but also a specific time.
Classic was one specific period preceded by Baroque and followed by the Romantic period.
The "classical period" is just one of many periods.
Bach is not classical music for example. It's Baroque.
But then of course the colloquial use of the term is so vague and mostly nonsensical that it might just extend towards the Beastie Boys in a few hundred years. So what do I know, really.