When will Dreamcast, PS2, Xbox, and GameCube become retro or are they already?

I am split of how I feel about the 6th generation consoles being considered retro. The types of games and graphics do not feel as far away from what we are experiencing with our current generation of consoles as the Saturn, PS2, and N64 do. The consoles of the 6th generation are around 14 to 16 years old now, but the generation went on much longer than the previous one, especially with the PS2 library having it's last release as recently as 2013 (FIFA 14). The Dreamcast almost feels like it could be included because it was released 16 years ago and had such a short life span.

I am wondering what the feeling is in the tribe here. Do you feel these consoles have hit the point in time that we can consider them "retro"? We are now on the 2nd generation separated from them, does that have an impact on classifying them?