Definitely gen 7. Wii is better than WiiU. PS3 is better than PS4. PSP is better than PSV. X360 is waaay better than XOne. The only system that might be better generation over generation is 3DS over DS. Sony first party games are less impressive. Xbox first party games are less impressive. "AAA" games in general are less impressive. The good news is that "indies" are arguably of equal quality or maybe better, and Nintendo software is as great as ever.
But, overall, games are getting worse :(