Real talk, outside of showing off good video and some surprises these Nintendo Directs barely count as advertising.
That being said, unless Super Mario 3D World pulls a miracle, Nintendo probably would do well to write the system off. The botched launch, plus costs along with nearly zero 3rd party support or revenue make it probably a bigger drain on their resources then being the ones to translate and distribute Level 5 and Square Enix games outside of Japan.
Besides if they really don't have anything, it is better that they don't embarrass themselves by claiming a 30 sec trailer to a upcoming Wii U title is worth significant time in one of their directs.