There were talks about that, but I'm not entirely sure it was implemented. Ask Yoshi on that one.
What I can tell is that Classic tracks are those tracks that became iconic and gained a lot of traction, generating fierce competition over the course of the years that eventually kinda dies down (maybe because the track is pretty optimized, maybe because the track is pretty old), a point in which someone (I'm pretty sure is we the mods, but I haven't ever given classic status to any track) decides that the track is indeed a Classic. For two reasons, actually: Reignite competition (there's a bunch of classic hunters in the exchange) and give the track a particular recognition.