With generations lasting twice as long in video games now, it would seem to make sense that video games would take twice as long to become retro. Give them time. PS2, GCN, and Xbox are retro now. It typically takes about two generations for something to go retro.
Plus, even once video game technology plateaus (which is still a ways off), styles and trends will change. That will make the older styles and trends "retro".
Also, discontinuation date seems to matter just as much if not more so than introduction date. Elcaset, for instance, was an audio format that used tapes about the size of a VHS tape and competed with regular cassette tapes. Elcaset was introduced in 1976, cassette tapes were introduced all the way back in 1963. But Elcaset is seen as much more vintage than cassette tapes, because it was discontinued by 1980 whereas regular cassette tapes were still commonly used all the way through the 1990s (though cassette tapes are vintage themselves now). Beta tapes were seen as vintage long before VHS even though they both came out in about 1976, Beta was gone by the end of the 1980s and VHS was still common until the mid 2000s. CD's themselves might not be considered vintage yet as they were regularly used until fairly recently especially in cars. My 2011 Honda Accord still has a 6 CD changer.
Video games seem to be the same way. I remember PS1 and Dreamcast going retro around the same time even though Dreamcast came out four years later. My Digital Press Buyer's Guide from 2002 says that NES was just beginning to become retro at the time, while Master System had been retro for a while by 2002. Again, it's because the much-more successful NES was viable for longer with people still paying big money for new NES games into the mid-1990s while the Master System barely made it over the 80s/90s decade line before being canned. The Wii seems to already be headed into "retro" territory before the PS3 and 360, even the Wii U seems to have only a few years left before it's "retro".
Despite the Wii getting new games all the way up to last month, the system faded from the new gamer's eye in the early 2010s. I would definitely say the Wii is more of a 2000's console than a 2010's console. It sold the most from 2006-2009 and the pace of new game releases dramatically slowed after 2011.