Super Mario Maker was the game the Wii U should have launched with. It was a legit killer app, something new and fresh after the 'New Super Mario' series had gone stale with 2 games in 1 year, and it made great use of the gamepad. If it had launched in November 2012 instead of summer 2015 the system might have had a chance. But I don't think Nintendo was even considering such an idea until it was obvious that the Wii U was unsalvageable.
One thing about the Wii U's failure is we did get a lot of AA games that Nintendo would never have greenlit on a more successful system. Hyrule Warriors and Captain Toad were made because Nintendo was desperate to get games out on the system. The quickness with which what became Tokyo Mirage Sessions was announced given that there was nothing to show for years also speaks to Nintendo realizing they had a problem. Even getting Bayonetta 2 announced before the Wii U launched may be a sign that they realized they didn't have enough games relatively early on.