That might be a big reason for it yeah. Here's the numbers for the holiday period.

DS had a crazy December in 2009 so when that loops round it will regain all of the ground the Switch has gained here and then some more.

By the time DS has finished it's 2009 holiday season it will be at 120.6m sold, and it will be 9th April 2022 for the Switch, which judging by the shipments will be at about 106.5m, 107m max by that time so still 13-14m behind the DS.

2022 is a chance for Switch to start recovering ground but the DS still sold 20.6m in 2010 so it's going to be a very tough battle.

So, from what I can see, even if Switch ends up being flat YoY from 2020 they will still end the year being around 5-6M units away from NDS, then the NDS will have it's 2009 holiday period which, by years end, will be at 120M units.

In the near future, unless Switch has an absolutely stellar Q1 start, Switch will likely be almost 14M units behind DS after DS's holiday period. NDS sells another 21M in 2010, and then just 13M the remaining years. If Switch can sell 20M in 2022, then it would need another 27M lifetime to outsell Nintendo DS.

For me, this is looking more and more unlikely, and I'm sticking to Switch ending at the 135-140M mark.

Edit: Woops, looks like you beat me to all of this above!

I think everything comes down to Nintendo's choices for Switch's end of life.

Will the Switch get substantial price cuts? Or like the PS4 will it not.

Will the Switch get a Switch Pro? Seems a bit late for that to me.

And the one that will have the biggest effect, when will the Switch successor launch. Holiday 2023? Spring 2024? Holiday 2024?

It's basically these 3 things that determine whether it's going to sell about 135m or if it has a shot at getting to 150m+

10 million LTD before the year is over seems like a really big accomplishment for Xbox, especially given how poorly (to my understanding, looking through some of the past data available on this site) the Xbox one has been doing the past 2-4 years.

Also continually impressed by the switch. Really impressive legs for a console that is approaching 6 years old

I am off, I don’t know why I thought it launched in 2016 

Nintendo could still release a switch XL. They did it for DSi and 3DS/2DS so why not Switch

That is true, the 3DS effectively killed the NDS momentum, particularly when they announced the price cut. Right before the price cut the Nintendo DS had sold about 4.3M, which, based on trajectory, means it could have sold about 12-14M that year, but it only sold 9M because sales dropped significantly after the announcement of the price drop for 3DS. 

Personally, I think that a price cut would be the largest factor because the Switch's largest area of potential growth, Europe, are historically more interested in lower priced Nintendo products (NDS, Wii, Gameboy). Switch is guaranteed to be top 3 in NA (13M from number 3), Japan (2.3M from top 3) and RotW (2.1M from top 3), and will probably end up in top one or two in at least two of those regions. In Europe, however, they are about 23M from the top three. It's taken the Switch over 4.5 years to reach 25M, so, with the current pricing model and trajectory, it's pretty doubtful it will reach that third spot. Likely it will settle around 5 or 6. 

You can get a Series S for less than a Switch, and a PS5 DE for just 100 more in most of Europe. So I think this is where the Switch will falter unless Nintendo starts targeting them more. 

That's basically what the OLED is though. 7" screen instead of 6.2". I don't think there's a need for larger than that.

Japanese comparisons have been updated to the latest numbers.

PS5 vs PS4 vs PS3 (Japan)

PlayStation 3 Week 56 = December 1st 2007
PlayStation 4 Week 56 = March 14th 2015
PlayStation 5 Week 56 = December 5th 2021

PS5 has completely flatlined with no stock available, to show how dire the situation is. Latest 5 weeks vs 5 weeks prior.

Week 47-51
PS5 - 86k
PS4 - 77k

Week 52-56
PS5 - 30k
PS4 - 156k

This latest 5 week period sales have dropped to a third of the previous 5 weeks, and it went from slightly outselling PS4 to being outsold by PS4 launch aligned 5:1. Japan is in desperate need of stock.

Xbox Series vs Xbox One vs Xbox 360 (Japan)

Xbox 360 Week 56 = December 30th 2006
Xbox One Week 56 = September 26th 2015
Xbox Series Week 56 = December 5th 2021

Speaking of no stock, the Xbox Series X/S has it's 2nd week without stock, this might not have lasted as long as the PS5 stock situation yet but we'll see how long it takes them to return to their 2.5k-4k weeks they were posting before.

Switch vs 3DS vs DS (Japan)

Nintendo DS Week 249 = September 6th 2009
Nintendo 3DS Week 249 = November 29th 2015
Nintendo Switch Week 249 = December 5th 2021

Switch posts a fantastic week that is barely down on last years. It will be interesting to see how Switch's December this year matches up to DS's December 2009.

Tagged and subscribed, great thread idea