It's trippy when you think about it. I would not consider Halo 1 a retro game, but it came out 13 years ago. In the year 2000, The Legend of Zelda was a 13 year old game (in the US at least) and I think everyone in the year 2000 would have considered it a "retro" game. The graphical leap from 2001 to now is certainly less drastic than from 1987 to 2000, but the span of time is the exact same.
Also this topic made me sad because we don't have N64 Virtual Console games on the Wii U and probably never will.