DDR3 is not "retro", for chrissakes.
It was 17 years old, or 14 years since wide distribution in the USA.
What counts as "retro" basically comes down to when the person you ask was born.
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.