Most likely, the Switch will rank #5 at the end of 2021 and #3 at the end of 2022.  I think it is obvious to almost everyone at this point that the Switch's only real competitors are the DS and PS2.  Obviously, I still think it is going to take the top spot. 

It will be interesting to see how it is doing at the end of 2022 though.  By that time it will be clear that whether 1) Switch is clearly going to take #1, 2) Switch is clearly going to take #3, or 3) it's going to be a very close race down to the very end.  I personally don't really even see 2) as an option though.  I am more curious to see if Switch is going to blow past everything or if it's going to be a very close race.  I didn't make this prediction thread over 3 years ago for nothing.

There are a number of differences between PS4 and NSW though. If NSW does 30mil this calendar year it’ll be at 110mil (insanity) 2022-2024 would have to make a complete drop and have jumped off the highest cliff in the world if it couldn’t get past 135mil at that point. The floor on this thing is 135mil, and that’s being generous unless Nintendo decides to kill off the NSW which Sony did due to the competition with MS. Something Nintendo has to not worry about anymore (from a direct stand point of view)

I don't think 200M can be too crazy, if the 3DS hadn't shown up, we could have seen that a long time ago in my opinion:

The sold 230M together, The NS is basically having an equal trajectory to the DS the first 4 years (only 1.3M difference). I say that 200M is well within the possibilities, that is if Nintendo doesn't release a SwitchU in a couple of years.

Nintendo kills early DS and Wii. But the pipeline of production of four consoles is not easy. 

The bad transition the DS for 3DS is cleary. 3ds free glass kill partially the popularity of DS. The 3D gave the direction of games too. 

I think it will end up between 140 and 180mil.

I can see 200M+ as a possibility.  For me, just barely beating the PS2 is a conservative scenario.  Selling 200M+ is possible, but definitely on the optimistic side.  Switch is at the 4-year mark right now, and it still has several advantages over the DS at it's 4-year mark:

1) Switch still hasn't had a price cut on the base model.  People will still pay launch price for the launch model, and they don't even need a game bundled in.  Nintendo is still having trouble keeping the base model in stock in spite of all of this.  They have a huge amount of room to bundle games and/or cut the price over the next several years.

2) Nintendo used to have to support 4 systems during transition years, and so they cut support for systems like the DS and Wii early, before the successors even released.  They don't have to worry about this even more, because they only have to support 2 systems during a transition.  Nintendo even gave some support to the 3DS during 2017 and 2018, after the Switch's release.  If they would do this to a system which only sold 75m total, then how much more are they going to support the Switch, considering it already outsold the 3DS in less than 4 years.  The 3DS still had a couple of years of decent sales even after the Switch released.  People should expect Switch sales to still have some momentum even after the Switch 2 is released.

3) Third party support for the Switch is already better than the DS.  Wikipedia lists the DS at 2030+366 = 2396 games (physical+digital).  Switch already has 3305 games.  It also seems to be getting more software each fiscal year compared to the last.  The current FY may be the exception, because of delays due to COVID.  However, all indications are that the next fiscal year is going to get a lot more third party games than the current one.  This is another significant factor that keeps momentum going.  If a system keeps getting a lot of third party games every year, then it's going to keep selling.

So basically, the Switch is a better position than the DS when it comes to price cuts, first party games and third party games.  These are the big 3 factors that determine any system's success.  It very well could just keep selling all the way to 200M+.

Number 3 is pretty much guaranteed.

As for number 2, Nintendo hasn't announced much during the pandemic but instead said that many things were in the works, so I guess we'll get a nice load of game announcement at their E3 presentation this year.

And about Number 1, does it really? 3 Reasons why I think this doesn't have to be:

1. If you include the inflation, $149.99 would be more comparable to the cheapest PS2 price, so let's set this as a more realistic bar. But even then,
2. Did the PS2 and DS really sold that many consoles at that price tag to make much of a difference? I very much doubt it.
3. The much cheaper Lite gets outsold 4:1 on a normal, non-supply limited day in Japan by the $100 more expensive base model, and I'm sure the rest of the world have similar ratios. So I think the value proposition is much more important than just the raw price.

I agree (with the bold).  Furthermore, I've changed my mind on Mario Kart 9.  I used to think it wouldn't come to Switch.  But the Splatoon 3 announcement made me think again.  If Nintendo is bringing 2 Splatoon games to the same platform, then I don't see why they wouldn't bring Mario Kart 9.  In general, all of those people who said, "Nintendo has already fired all of their big guns" didn't realize that Nintendo is reloading and is firing off a lot of those big guns again.

people don’t understand that Nintendo might of fired off most of the big guns, but as you said there is plenty more notable potential releases that can come. Add to the fact that evergreens play a huge role into NSW lifespan, this further helps mid size releases as well.

anyway let’s play this game...

+BotW2

+Splat3

+Rhytym Heaven 

+Tomodachi

+Metroid Prime (this could be a blockbuster hit if cards are played right)

+Pokémon Arceus (new kind of mainline game)

+Pokémon Gen 9 and more

+Mario Kart 9 

+ XC3 (or new IP)

......

Good takes by both of you.

And yes, Mario Kart 9 on Switch is still very much possible, though not a given. The heavily rumored Switch 4K model is supposedly coming in September of this year. That makes me think that Switch 2 won't launch until at least November 2023, if not March or November 2024. 

Mario Kart 9 could come out on Switch (probably 2022, maybe 2023) and then have an enhanced port released on Switch 2 right at launch or in the launch window. That way, you could stretch the game out over two platforms. I mean Nintendo did that with Mario Kart 8 after all. And that way you have a killer app (even if it's not a truly new game) available right on Switch 2 at the start. Mario is Nintendo's biggest IP, and more specifically Mario Kart is.