The interesting thing is how much the Switch really hasn't needed new or experimental IP to drive that sales success.

Aside from Ring Fit Adventure coming at a time where most people can't or won't go to the gym because of COVID, pretty much all of the other top selling Switch titles are pre-established Nintendo IP that aren't really trying to break the mold that much. Many are even just Wii U titles remixed or spruced up a bit and then you have like a collection of 10-25 year old Mario 3D games selling 9+ million in just a few months.

I thought maybe Mario Kart Live might take off and sell big, but apparently not. That's something while tied to an established franchise is conceptually quite different/experimental. But nope.

Switch will probably end up with 20 ten million sellers.

It's already got 11. Luigi's Mansion and SM3DW will both hit it this year. That's 13. Too bad they didn't leave 3D All Stars out until end of year as it fell just short.
MH:Rise will hit it. That's 14.
The Pokemon D/P remake and the Pokemon Legends game will both hit it. BotW2 will obviously. That's 17.
Splatoon 3 has a good chance of hitting it. That's 18.
Eventually they'll no doubt release a brand new 2D Mario game. That'll be 19.
Lots more options for just one more game to get there: maybe Pokemon Snap does it?? Another 3D Mario?? Another Ring Fit?? Another Mario Party obviously would. Also definitely the possibility that Mario Maker 2 slowly creeps up to 10 million.

Could very well see as many as 25 ten million sellers when it's all said and done.

I'm pretty sure Minecraft sold well above 10mil on the Switch, so while we unfortunately have no confirmation, I think the Switch has twelve 10mil sellers.

Switch has 11 first party titles over 10m+ so far.  Luigi's Mansion 3 is at 9.59m right now.  It's going to cross the 10m mark sometime this year.  Monster Hunter Rise will cross 10m+ with the way it's selling.  Minecraft will definitely sell 10m+ if it hasn't already.

I count 14 titles that will definitely sell 10m+ that have already been released.  Both Mario Maker 2 and Super Mario 3D World have a decent shot at it as well.  This is all before counting any titles that haven't been released yet.  I think Switch is guaranteed to get at least 20 titles that sell 10m+ before all is said and done.  There is plenty of life left in the system.  If things go really well, it might get more like 30 titles in the 10m+ range.

BOTW broke the mold of its series pretty drastically, which is arguably the main reason for its success, that it revolutionized the series instead of just sticking to the established Zelda formula.

I meant more in the sense of Wii really was centered around Wii Sports, Wii Fit, the DS around Nintendogs, Brain Training ... that sort of thing. 

The Switch more or less is basically just driven by established Nintendo IP, although Zelda: BOTW offers new things for the Zelda IP, like having a more open world style akin to more modern games like Skyrim, it's still very much a Zelda game. 

It's only vaguely like a Zelda game with the closest comparison being the original even then it's widely different. BOTW's main draw is the freelance gameplay mechanics they are on such a deep open level that the is no other game that allows the same freedom of depth in one package not even GTA or RDR, the open world aspect is just one small factor in it. 

That's a good point, I did overlook the first two, though I have a feeling the third will fall just short.

That would make for 16 total just given what's been released and announced so far, and there's likely still several we don't know about yet.

It may well reach 20 and double the Wii and DS.

I could see that total climbing up to 20-21 by the time the Switch is done.
Including the 11 we have now, the other 9-10 could be Luigi’s Mansion 3, 3D All Stars, 3D World + Bowser’s Fury, Mario Maker 2, BOTW 2, Splatoon 3, Pokemon BD/SP, Pokemon Gen IX, Monster Hunter Rise, and the next 3D Mario game. (Whether it’s Odyssey 2 or a Bowser’s Fury styled standalone.)

3D All-Stars is discontinued. This was the final shipment number.