No, actually, it's a classic because of how it changed perspective on games. Whether it's 3D or not is completely irrelevent. ALttP is a classic because it completely changed how Zelda was looked at and played. OoT is a classic because it did the same exact thing, be it in 3D or not. Same goes...
Of course it's a classic.
A decade after it's release, and it's never been out done by any other Zelda game (IMHO), and it introduced so many new featuress that are still used today. (Z-targeting)