Mind you as someone who was actually around during the GameCube era I remember the exact same excuses being stated at the exact point in the GameCube's lifecycle, lol.
"We can't judge the GameCube yet! Wait until Zelda and Mario Kart! Those were huge for the N64!".
And just like NSMBU "doesn't count" (fanboy logic), people were also saying Mario Sunshine "doesn't count" because it wasn't a proper Mario. That may be so, but that's what Nintendo brought to the table by their own choice.
What's troubling about the Wii U is the lack of acceleration when it DID get better releases, by any estimation the last 4 months for the Wii U were pretty darn good -- Mario 3D World, Zelda: Wind Waker HD, Pikmin 3, Rayman Legends, Sonic Lost World, Wonderful 101, Wii Party U, Wii Sports Club, Just Dance 2014, Assassin's Creed IV, Splinter Cell Blacklist, LEGO Marvel, Call of Duty: Ghosts, Batman: Arkham Origins plus a $50 price cut, better main bundle, and better TV marketing.
All that and all Nintendo has to show for it is a extremely weak 55k in October and 220k in November during the holiday ramp up. Trust me, there's not much joy at Nintendo HQ over this performance, it's worse than the GameCube's worst November ... even fall 2005 where the only "big" release it had was another Mario Party.
This is not indictive of a system that people love and are just waiting to get some games going.