Since when did the Wii's online problems have anything to do with the lack of online players on Wii U? And the retorical question.. Are you going to buy a system which has 2 people for an online play community, or are you going to buy a system which all your friends already have and play? You see, it's not always about convenience, it's more about where your friends community is, and it's not on the Wii U for most people. That's why there's no one playing AC3 online, and games such as Batman and others wont have online multiplayer, because there wont be any players anyway.
Yes, I will agree you can buy the system where your friends are. (Why you would buy just for your friends and not yourself is kind of silly to me. It is not what your friends want to play, but what you want to play & enjoy). Problem is not every gamers so called friends are gamers too. Nor does everyone have a computer by to use a voip program such as skype, so you can search all at once, or want a phone bill via long distance or not just to get a game going (Heck, look at how people refuse to call each other now with all the silly texting. Of course texting is an option too, but not everyone wants to pay for text charges or a texting plan). If the Wii U had a chat system that carried over into games you could make the whole connecting to games easier if it did the whole searching for friends crap like most of the Wii games. (Also, I know Wii U has inviting systems, but that again is a bit cumbersome).If they did it would likely lack support for USB mics with some kind of Wii Speak crap required just to use it. Which I guess that would not be such a problem if you wanted to talk to just friends, but what is the next game gets a special headset like the Wii spliting the community so you can't easily make new friends. I for one don't just add anyone to chat without knowing how they behave in game. The last thing I need is to add some crazy screamer or stalker type to get hounded. (Oh and I already have an internet stalker. That has made countless new accounts spamming me with add friend messages, trying to get me to add them again on the 360/PS3. Love the block button, but still having to do that multiple times is a pain. It is not as bad as it use to be, but the guy still gets me out like two new friend requests a month).
Convenience is a deal breaker for most alot of people in this western world today. If it is a paragraph long it is "TL|DR", if they can't find it they just give up (Can't tell you how many times I have seen this happen. Specially on mic push to talk settings on the PC), if it is even remotely a little complex, "I can't do it and shouldn't have to", et cetera. If it was more seemless you would find more people checking in because of something as silly as "I don't understand" can keep a majority of the more casual time to time gamers away. Sadly, this is just how it is, like it or not. (Also, in no way am I saying everyone is not playing for this. There will likely always be a few, unless the game just didn't sell well).