The Xbox 360 ended production during the 2016 year on April 20, 2016.  So it was still in production for almost a full 5 months and then there would have been plenty on the shelves to close out the year.

The 3DS ended production towards the end of 2020 on September 16, 2020, is why it was able to sale remaining stock through 2021.  

Again the Xbox One ended production in 2020, 2021 the following year to sale existing stock already passed.  It is now 2022 starting the 2nd year after ending production.  There is no chance that 120,000 units are still sitting on shelves, therefore no way to reach it. Why not compare it with Xbox 360 year 2017 to at least put it into a similar time frame?

Additionally regarding the poll, the Wii U ended production in 2017 on January 31st 2017, so to keep it on the level it should be compared with 2018 Wii U sales.

You do have a point, that sales were notably limited due to lack of stock. However, even with the stock issues figured out I think people are overestimating it's sales numbers. Currently, the console sells out quite a bit due to the limited stock phenomenon (where people will buy something that they may have waited for because the stock is currently limited). Not saying the demand is "artificial" or anything like that. It's definitely there, and sales would absolutely be higher without stock issues. However, a 19M+ year for it's second full year on the market is a VERY lofty goal for any console. 2019 is technically Switch's third year on the market, which is partially why it hit that goal (among just having a stellar year software wise and, of course, Pokemon). Sony is looking to have a great year software wise as well, but unlike Switch all three of it's best sellers will be on another console which people own (PS4). In addition, it took Sony until 2017 to have a 19M+ year for the PS4 when it's competitor practically shot themselves in the foot. It would be difficult for the PS5 to do that in half the time when it's competitor is doing substantially better image wise this generation. 

Anything can happen, and if Sony sells 19M+ consoles in 2022 then that is freaking awesome. I just don't believe they will or that they would even if the stock were figured out. Just my two cents. 

My bets:
PlayStation 5 vs Nintendo Switch'19 (19.2M):
Winner: Switch 2019.
PS5 stock issues.

PlayStation 4 vs PlayStation 3'16 (670k):
Winner: PS3 2016.
PS4 in Japan sold 70 until now, even without PS5 stock issues.

Xbox One vs Xbox 360'16 (390k):
Winner: Xbox One,
still good machine for gamepass, or even cloud

Xbox Series vs Xbox 360'08 (11.1M):
Winner: Xbox Series
Series S sells when the others dont have stock

Nintendo Switch vs Nintendo DS'10 (20.5M):
Winner: Tie.
I expect Switch to sell around 20.5

If Xbox keeps selling like this 12 million might not be out of the picture.

Yeesh, Sony's numbers are really not looking that great rn. At this rate, Sony might only ship what Switch did in 2017. Really hoping this improves.

Looks like Switch will win both of it's comparisons.

PS5 not looking too hot, and I don't know if it can recover from it even if the shortages would end now. The next 2 months it needs to catch up to the Switch or else the train will have left the station already.

They should have released the 3DS in holiday 2011, not in February. That way they could've launched it with Super Mario 3D Land and Mario Kart 7 and it would've started out stronger. Instead they originally planned to launch it in holiday 2010.

True, but I think Nintendo had their eye on Sony releasing the Vita in holiday 2011 and wanted to have a new handheld on the market before then.  Sony had gained an impressive foothold in the handheld space with the PSP, so Nintendo likely wanted to get a headstart on the next generation of handheld tech.  The same way they cut the legs out from under the Gameboy Advance, which had sold well in a very short period of time, in order to counter Sony's launch of the PSP.  

Makes sense that Nintendo wanted a headstart with the 3DS, but I also wish that they waited until Holiday 2011 or even early 2012 to launch it. They could've even waited to announce it until E3 2011 (so it would be after Pokemon BW's launch) and they could've announced Wii U at E3 2012.

Honestly surprised with how well Switch is keeping up with DS right now. If things continue Switch will not only match but exceed the DS's totals.

Also, congratulations PS5. You are catching up to the PS3. Looks like manufacturing has indeed improved. If they keep this up they should be able to hit much higher than 10M. I believe my estimate was 12-13M for this year.