Sorry, but this is a really silly thing to say. The Wii got and is getting a lot of support from major series and it still doesn't do much for reaching a certain target group.

Some examples:

Winning Eleven. Major series from Konami, Wii get's a version made for it, makes excellent use of the Wiimote, gets great reviews, sales in Japan still less than spectacular. The Playstation versions, which surely took less effort, still outsell it too.

Monster Hunter 3. This one did great, actually, but it wasn't really due to it being on the Wii. It almost doubled the sales of the previous console installment but I think this is mainly thanks to general growth in popularity it achieved on the PSP and the fact that more people have online nowadays than during the PS2 era. Capcom has been clear about this from the beginning, but it was put on the cheaper to develop for Wii rather than the PS3 because most of the money will be made with the PSP ports and a straight port is always cheaper than a down- or upport.

Which brings us to arcade games like Tekken or SF4. These are traditionally put on consoles which roughly match the graphic capabilities of the arcade boards. Downporting takes more effort and time than a straight port where you can mostly use the assets you already have. Also the better looking version is likely to sell more too so where would be the point of including Wii for multiplatform releases of these kind of games? Wii exclusively got TatsuCap for exactly this reason.

Sega supports the Wii with Sonic games. They do decently well. Because they cater to families.

The Wii is getting a fair share of RPGs this generation, Tales of Graces being the best example. Definitely an a-grade team. Still, Vesperia already sold more games on the HD twins than Graces will ever do (unless ported to the PSP). And judging by effort I think development costs weren't that different between Vesperia and Graces.

Crystal Bearers, while experimental, has the FFCC brand name and Kawazu involvement, the former having achieved several hundred thousand copies sold when it came out and the latter topping one million with many of his releases during the 16- and 32-bit era. It shouldn't perform as badly as it is doing. The audience just doesn't seem to be there.

Resident Evil spin-offs, while deviating from the series formula and definitely not being developed by a-grade teams have done much better than a lot of the more serious efforts.

Playstation still makes most of its sales with tweens. Nintendo's console still makes most of its sales with families (i.e. kids, parents and now also increasingly with seniors). The fact that Nintendo could climb from a distant number two with the GC to clear number one with the Wii and already doubled the sales of the GC is because they made the right decision to maximize the sales potential in the target group where they were always strong. They still fail to reach the tweens though and everybody should be able to tell why. The young adult gamers just don't want their games on a Nintendo console which is still perceived to be kiddy.

Sony isn't losing this badly because Nintendo is stealing their main target group. It's because the high price was a stupid decision, we can see that by the sales growth achieved just by lowering the price to a reasonable level. It still is too expensive though.

Nintendo did everything right except for keeping the price too high for too long. I think NSMBWii will do very well and the Wii will keep reaching its audience but it simply isn't the same as the PS2 had. I think it's save to say that Nintendo shouldn't waste money on money hats and 3rd parties being reluctant to put their tween-targeted franchises on Wii were proven right (see especially MMV's case). Nintendo still is gaining customers in the young gamer/core market, let's see how many of the "non-"gamers Sony can reclaim with the wand and family-friendly software once their console becomes cheap enough to be able to reach that market again like they did with the PS2.