8-10 million seems highly unlikely to me. 

The product itself just doesn't seem all that trendy and marketable. Something like Wii Fit was elegantly simple and had very effective branding, it was almost iphone-esque in how is sold itself as a must-have lifestyle accessory.

This on the other hand just doesn't feel like it has that X factor. From the name to the look, the branding just doesn't seem catchy or desirable.

I could see it hitting 3 million at a stretch, but that'd be the upper rather than lower bounds in my estimation.

So basically any franchise that you don't like was never popular anyway. Ok, great logic. Apparently you were in a coma from 1991-1994 as well when Sonic was clearly one of the most popular characters in gaming. I remember even reading that at one point Sonic had overtaken Mario in popularity during that period. Not to mention you couldn't freaking watch TV for more than 10 minutes before seeing a Sega Blast Processing commercial with Sonic in it. 

The point is saying everything can bounce back because Super Mario Bros. did it is just a dumb statement. It's like saying every film 40 year old film franchise can bounce back and make $2 billion dollars because The Force Awakens did it, so it means "Jaws Awakens" or "Godfather Awakens" could do similar business. Uh ... hell no. 

Labo was not a big success. Bottom line. And nothing even close to the Wii/Brain Training era of successes. Couldn't be any further away, Labo kits are sitting collecting dust in discount bins, I don't think the initial shipment in Japan even sold through, lol. 

Video games are for kids ... and adults. This is also a "fitness game" and fitness trends change too. Again how many fitness fads have come back into vogue lately? P90X the new hot thing still? How about the Thigh Master? Seeing any commercials for 8 Minute Abs these days? Ab Doer? Nope. Women still lining up to buy Jane Fonda aerobics videos? Nope. Because fitness fads are "fads" for a reason ... people move on from them and want to try something new and different. Thinking a video game can make you lose weight went out of style almost a decade ago now. 

Bubsy was btw a GOTY candidate for 1994 up there with DKC. 

Yeah, I forgot Sonic Mania. Now, outside of Super Mario Bros (including Mario Maker), Shantae, Shovel Knight and Sonic Mania, what other 2D Jump'n run can you name?

At bolded: Well, there's your problem. See your hypocrisy? You say it comes and goes, yet state right after that that people moved on from it, with the clear implication that it never comes back, contradicting your previous sentence in the process.

Oh, and for what it's worth, my wife is still (or, dare I say, again) on an Atkins Diet...

I'll say this though, I do like that they've made it a new IP instead of just "Switch Fit" featuring the Wii Fit trainer or "Mario Ring Fitness."
Whatever else Nintendo can be accused of, between this and LABO, it certainly can't be said they don't make creative new IPs,

I feel like people put waaay too much emphasis on "fads," "trends," etc.. If something's a good/interesting product, it's a good/interest product. And that will shine through. Even if said product might be hitting a scene that is isn't currently in line with its sensibilities, it can transcend that or even help nudge trends towards a NEW paradigm shift if it's great enough. It's also fulfilling a human need, which will always be there - to lose weight easily and in a fun way (or at least in a means that isn't excruciating).

Hell, look at Star Wars for instance. Lucas launched that film into a scene where dark, gritty movies filmed with anti-heroes were the thing - space fantasy was almost a non-entity since Flash Gordon, and what little major sci-fi did exist was usually also of the dark, dystopian nature. Very anti-Star Wars if anything..

Now, obviously not saying this strange ring-fit-RPG game is going to be anywhere near that level of course, but my point being that I think looking at current "trends" to garner the success or failure of a product is silly and missing the bigger picture. Either something is good or it isn't, and people respond to that regardless. And I don't think Wii Fit (and especially this new game) shouldn't be compared to fitness "fads" like P90X. It's still a game at the end of the day; just a game that's centered around fitness. 8 minute Abs and P90X aren't games, and certainly aren't too fun..

If Ring Fit is a fun, well-crafted game, it'll succeed. If not, it'll fail. Simple as that. Again, I certainly don't anticipate to move even half the units Wii Fit did, but I do think it has potential to be successful, and perhaps help further spur the fitness genre in gaming, potentially leading to some more interesting and intricate fitness games.

It's annoying that due to a lack of software tracking we may never know its actual sales. I miss the days where we could put a number on how much something sold; even if that number wasn't always 100% accurate it was nice to have some idea of how any given game performed. 

This!

Sorry, if I disagree to the idea of the Wii-crowd being gone I don't speak about IPs. You are right, IPs come and go. But gameplay principles that people were interested years ago are most likely something people are interested in today. For instance, many people are interested in the gameplay principles, that the game presents you the targets, probably moving one and you take aim and shoot them. 40 years ago it was possible to implement this gameplay principle into a game named Space Invaders. And you're right, nobody wants Space Invaders anymore. But the Space Invaders crowd isn't gone, these days it plays CoD, Battlefield, Fortnite and PUBG. Just the games that are technical possible these days implementing these principles.

So if you say the WiiFit crowd is gone, I ask where. If you would say they now play all EA Fit, then I would say for Nintendo to win them back they need to innovate. But I just don't see where they might've gone.

For some more examples:

• Guitar Hero →a shitload of different rhythm games and even combinations with other gameplays, like Roguelike in Crypt of the Necrodancer
• Metroid+Castlevania →a lot of Metroidvanias, including but not limited to Hollow Knight, Dead Cells, Guacamelee, Steamworld Dig and Bloodstained
• LucasArts adventures →point&click-adventures where dormant for a while, but now have many games and evolutions of the main gameplay concepts like Syberia, Oxenfree, The Telltale games, Phoenix Wright, Professor Layton, Portal, L.A. Noire
• isometric RPGs →were also not much for a while, but came back with games like Divinity, Pillars of Eternity and now Baldur's Gate 3
• Pacman → at it's base Pacman is a time-pressured puzzle game, it was replaced back in the day by Tetris and Puyo-Puyo, and now we have so many different of these

So it is the same story. Companies and IPs might die, but the crowd playing the games isn't going anywhere. You might have to readjust or sometimes innovate to keep the gameplay-ideas alive, but the players are still there.

As long as it sells at least a million, Nintendo will report it in the following financial report.  Although I agree that there is now a lack of long term precision, and I miss that.