So Japan is making up a large percentage of the Switch sales this year, momentum outside Japan has been kinda muted

I meant hardware, my bad.I already fixed it.

But who knows?Mario Party on its hayday used to sell millions upon millions of units.So if a game like that cant move the needle, then Nintendo dosent have alot of killer apps on its pocket.

Oh yeah!

Yesssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssssss

They still have quite a few guns left to fire; Animal Crossing, traditional Pokemon, 2D Mario, pay off Capcom for an exclusive Monster Hunter, etc.

I am happy with this!

Personally, I would consider the Switch to be a great success, not so much for how well the system itself has been selling, but for just how much greater it has done in the software department.
At the rate that their games are selling and if they continue to show fine leggage, the Switch is going to be the home of a lot of "Best Selling ______ game in the series/of all time"
- 3D Mario
- Zelda
- Splatoon
- Mario Tennis
- Xenoblade... and the Xeno series as a whole.
- Kirby
And potentially Smash Bros, Bayonetta, Pikmin, and Metroid Prime.

And that's before going into all the 3rd party titles, both Western and Japanese that have been selling well.
The Switch version of FIFA 18 is on its way to being the best selling FIFA game on a Nintendo system.
Skyrim has been a success.
The overwhelming success of Octopath Traveler led Square Enix to deciding to have that entire team devoted to making Switch titles.
Super Bomberman R was one of the most, if not THE best selling Bomberman game. And Capcom recently announced they're making a Monster Hunter game from scratch for the Switch. Plus there's Mega Man 11.

And then there's indies.
There's no shortage of software, and it would seem a lot of it is selling.

Unless they start bundling it with every Switch once its sales drop dead on its own. Then the possibilities for 1-2 Switch are endless. lol

Yes, but you still cut more than half that list if you are gonna nitpick what you define as an killer app.It wouldnt be a problem given this is just fun speculation if you didnt complain about Nintendo "mishandling" software releases.I mean, by your definition of killer apps, you could probably count in one hand the number of IPs that Nintendo has left that could be considered as such and you expect them to have one every 3 or 4 months?

Certainly there are titles, considered to be killer apps,that move more and some that move less, but if Super Mario Party is a return to form, and considering its past numbers, that is one potential hardware mover if I ever saw one.

I think Capcom might be way ahead of you on that one.
https://www.destructoid.com/monster-hunter-world-is-skipping-switch-but-it-sounds-like-capcom-has-plans-to-make-up-for-it-509959.phtml

Just having Animal Crossing in the first half of this year and having Smash in September alongside the online service would've made a big difference, then you could've had three killer apps this year spaced a few months apart just like last year.

20 million would've been a breeze then.