I think it all depends on how Nintendo supports the console in the later years, if the cut support like they stupidly did for the Wii then it won't pass the PS4. If they give strong support in the coming years then it's possible to equal or surpass the PS4.

Mario Kart 9 - 20m+

Switch Sports - 20m+

There's also the possibility that early Switch 2 games will be cross-gen. Is the next Smash or Mario Kart really going to be so demanding that the original Switch can't run them?

Why is a console going to be released to replace a portable? Fact is VB had nothing to do with GB the latter was the market leader and destroyed all competition sales were fine otherwise they wouldn't have waited 3 years to bring out the GBC again all companies are always working on the next platform. The VB was in development since 1991 it was always planned to come out With Yokoi having looked at the tech since 1985 it was never a GB successor it was meant to create a VR market in the same way the Game and Watch did which the GB went on to foster.

SMO and BOTW doing well does help down the line as they're still selling even now and helping move platforms the old well the sequel won't bring in new people argument is debunked by these very games as they outsold prior games heavily you know what that means? Everyone buying the games now is a new person buying the platform for them under your logic here COD and GTA sequels should never have sold more than the prior games.

Again BOTW outsold every Zelda game under what you claim the game should have sold more than 4-5m yet on Switch alone it's going to hit 20m LT this debunks the mode of thinking you're using another example is when people though MK8 wouldn't do that well because it's also on Wii U that game by the end of the quarter will be over 20m Pokemon is also another example. Your argument is not factoring in the knock on effect of having mainstream appeal.

I really doubt that Nintendo can repeat the Wii Sports (Resort) and Wii Fit success.

Wii Sports Club was a total dud (even if we take the much smaller install base of the Wii U into account) and Ring Fit Adventure still has to prove, if it can keep up good sales for a longer period or will be forgotten in a few months.

That was probably the most bizarre thing I've ever read on the internet on par with

"Smash Bros Ultimate isn't going to sell the switch since most of Nintendo hardcore already bought the system",

" Switch momentum will fall off the cliff after all of WiiU fans bought the system ",

" Switch sales will drop next year after releasing SMO, BOTW, and Splatoon 2 ", 

" Pokemon SwSh will not move hardware because every pokemon fans already bought it after Let's Go released " 

Its especially a weird take when games like COD & FIFA continue to sells systems with their 7th entries on PS4/XBO.

Y'all put way too much emphasis on counting exclusives seperately. The vast majority of gamers is casual ones. The ones that buys a console when it's a hot item in society or when it has deals and price reductions or new models. It's not really about 1 mario or 1 zelda but the accumulation of games.

The more exclusives you add, the more someone will be tempted to buy it. Some take more time then others and might need 2 Zelda games, so saying that with Botw already on it the second one wont have much effect is stupid. Also knowing Nintendo, there will probably be more collector editions in the future making fans buying multiple consoles cause it seems that you also all forget that people tend to do that. I'm sure some people have multiple PS4s and will have multiple Switchs, even more now with the lite adding a different approach so you can easily combine both in your lifestyle.

That lite effect still hasnt hit the holiday or a long run either, its brand new and for now switch sales have been enormous so let's see if the momentum continues next year with again huge titles starting the year compare to previous years where it was dry until june (except the launch).

Switch also had barely any deals. It is having its third BF and still same price but with 1 game. Nintendo can be way more aggressive than that and probably millions of people are waiting to buy a switch at a lower price or with more games and once these are at lower prices as well (Nintendo classic line).

And it has been reported that lite sales doesnt affect the classic ones, so the price point for the lite wont affect the number of potential buyers for a classic switch price cut. We can expect more models as well. 50 millions in before 2020 and there is still so much marketing possibilities and the momentum isnt slowing down with Switch having an incredible reputation in the gaming community in general, compared to what the Wii had.

So anyone thinking this is on par to 3DS, honey 90 millions is easily the floor for this one and the only thing in it's way is Nintendo releasing a new console too early like they tend to do sometimes with handheld.

Mario Kart 9 will be a Switch 2 launch title, book it, there's no reason for them to use that bullet for the current Switch as MK8 Deluxe is bringing in all the Mario Kart fans for this platform anyway.

I don't think FIFA or COD are primarily selling PS4/XB systems at this stage. If you're a FIFA or COD fan, you have a PS4/XB1 already, FIFA and COD are selling to FIFA/COD fans that already have a PS4 largely. FIFA might though in Europe as its more of a casual appeal game to some. 

PS4/XB1 continue to get new IP yearly though like Cyberpunk is going to be a big one, FF7 is basically a new IP in the fact that FF7 has notalgia appeal specific to that one title that other FF games don't have (there are lots of fans of FF7 specifically that don't care for FFXV for example), Sekiro is a new IP, Days Gone, Last of Us 2 etc. etc.

But it's not like when FIFA 2020 releases there's some huge boom in PS4 sales anymore, it's an expected title by now.