The indie scene has been steady. Sometimes delays happen and they takrle their time (Oddworld, Hyperlight Drifter, 90s Racer), sometimes there are cancelations (Project Cars, Gone Home), others price and decisions that don't go well with the community (like Space Hulk released last week without the additional content for $30), others are just starting (Binding of Isaac Afterbirth).
Yeah, it may not have many or the same games as the others (though the assumption that the Wui U should be able of running them just because is a bit naive). But that's kind of the point too. Indie games doesn't need to be "big, hyped games" that everyone knows of and are released everywhere.
As beril pointed out it is quite easy to have games on it and the games are there and are still coming, just that under the current circumstances some might prefer to not bother.
2015 ended with the release of FAST, which aside being a great game also exceeded sales expectations. Plus the overall indie scene on Nintendo platforms is segmented between Wii U and the 3DS, which received and is receiving great support.