New NES were still available in the US through at least Christmas 1992, and in Europe deep into 1995, both selling alongside the SNES since 1991.

The final new international games were released in 1994, but Europe still got new games into 1995.

Japanese Famicoms were still being sold in Japan when the PS2 released. They sold more in Japan in 2001 than in 2000.

So no, calling the NES "retro" in 2000 wouldn't have made all too much sense.