What? The Wii U may have been Nintendo's biggest home console flop in terms of sales, but it wasn't for lack of trying on their part. Poor branding and poor advertising early on, yes. But "dropped like a red hot ball of iron" is being disingenuous.
System Release: November 18, 2012
Discontinued: January 31, 2017
Some notable Nintendo developed or published games released in 3 year or later:
Mario Tennis Ultra Smash (2015)
Splatoon (2015) released in 3rd year of console's life as a brand new IP and launched a hugely successful new franchise.
Super Mario Maker was released September 10, 2015 and I remember a huge effort to push it with Wii U bundles in the 2015 holiday season.
Yoshi's Wooly World (2015)
The Legend of Zelda: Twilight Princess HD (2016)
Star Fox Guard/Zero (2016)
Tokyo Mirage Sessions #FE (2016)
Paper Mario Color Splash (2016)
The Legend of Zelda: Breath of the Wild (2017) released 2 months after the console was officially discontinued.
Nintendo also made an effort to collaborate with other devs to share IP's such as with Koei Tecmo on Hyrule Warriors and with Atlus on the aforementioned Tokyo Mirage Sessions. They also made an effort to publish games for other devs to bring exclusives to the Wii U at the time such as The Wonderful 101 and Bayonetta 2.
3rd Party developers may have dumped out of releasing games for the Wii U a year into its lifespan (EA never released another Madden NFL on the system after Madden 13 in 2012), but implying that Nintendo abandoned it just as quickly is highly selective memory.
4 years and 3 months isn't a long console life by any stretch, but there have been worse. The Dreamcast released in NA on September 9, 1999 and was discontinued on March 31, 2001. That's less than 2 years (still less than 3 years even if you had the 1998 Japan release).
Sony may not have officially discontinued the PlayStation Vita until 2019, but what efforts did they make to support the system beyond mid-2014 (two years into the systems life)?