You don't seem to realize that things have changed substantially because of these "flukes", though.
The Mario Kart brand, for example, has gone from having some 7m fans to some 30m fans because of the exposure it got on the Wii. As a result, MKU will be hugely popular and Wii U won't come close to nearing the "normal" low level of sales of Nintendo consoles. This applies to something like half a dozen of Nintendo's brands, at least.
The same thing doesn't work for PSP at all, though. Sony has no significant handheld brands of their own and the few that they had (MH) have been taken by Nintendo. As such, whatever headway Sony might have made with the PSP is likely to go wasted. Plus, with the PS brand as a whole so much weaker now, Vita will be even more helpless.
Also, calling Sony console king in the same breath as calling Nintendo handheld king is a bit much. Nintendo's handhelds as a whole have been far more and far more consistently successful than Sony's home consoles. The PS4 doing well isn't guaranteed by any means.