Wii/DS each had ten 10-million-plus sellers. Switch has five and it's not even 2 years old

[Slownenberg]

Switch should end up with at least fifteen 10 million sellers.
Done:
1. MK8D
2. SSBU
3. SMO
4. Z:BotW
5. Pokemon S/S
6. Pokemon Let's Go

Almost there (easily reaching this year):
7. Splatoon 2
8. Super Mario Party

Guaratneed from a known future game:
9. Animal Crossing

Possible already released games:
10. Luigi's Mansion 3 (likely)
11. NSMBU:D (maybe)
12. Mario Maker 2 (maybe)

Likely future announced games:
13. BotW2

Likely possible future games:
14. Another Pokemon
15. At least one more Mario 2D or 3D

And of course it's possible that there will be a 2D and 3D future Mario games released that both hit 10 million, adding one more to the above list. Possibly a fourth Switch Pokemon as well (though I'm really not sure about that as next Pokemon should be in a couple years and a couple years after that Switch 2 will likely be out). Maybe there will be another mega 10mil seller from a Nintendo franchise that hasn't come out on Switch yet. And maybe some game we don't even expect or god forbid a third party brings a big new super popular AAA game or even say like Ring Fit continues to have legs for years and creeps past 10 million in a few years.

So I'd say minimum is 15 with the max 18-20.