Man that is how things were back then. Look at Sega look at Atari consoles. They also dominated by first party games for most part. You are comparing a different period in gaming all together. When Playsation launchedm Sony used its only strength  as a new hardware company to make 3rd parties shine. This is how 3rd parties have grown into mega giants on consoles. 

They do try though. Problem is people assume they all suck. The ones I have listed eariler should have sold better.

They didnt.

Yet even after playstation existed the top 20 on Nintendo consoles remained the same - hence a trend.  The 64 and GC all had successful 3rd party franchises - Tony Hawk, COD, Madden, Fifa, banjo, Star Wars, etc. but the top 20 is still dominated by Nintendo.  

To say that the WiiU's top 20 is dominated by Nintendo solely because there is no 3rd party support is just silly.  It's always been that way.

'Not having the same support as playstation' is not the same as 'Not having support'.  

Well, DS and 3DS have some pretty strong 3rd party support, and i dont think its because they`re the only viable handheld systems. PSP did really well and had its 3rd party strong, but DS also had that.

That's what a third party game is

1st party owned and developed internally (like uncharted)

2nd party owned but developed externally (like bloodborne)

3rd party not-owned and developed externally (bayonetta 2)

At least in my book. And my book refuses all other doctrine

The OP has this backwards. The reason Nintendo games dominate the Wii U software sales is because it doesn't have any third party support. It also doesn't help that it's very likely that a huge number of Wii U owners own another console. Because realistically, if you're interested in anything but Nintendo games, you need another console.

It's an exclusive, but it's still 3rd party. Nintendo doesn't own the IP or anything.

I'm being sarcastic. Third parties have lots of room to release games