Yeah I did notice; thanks for considering it, I'd really love to see it and given the 3DS's total and the Xbox Series' trajectory thus far I think it'd be close enough to be really fun to watch play out.

I'm still getting used to seeing Switch tracking ahead of 3DS in Japan after being behind for so long.
Switch is proving far less front-loaded, and with the likes of Pokemon Legends and Splatoon 3 still to come it shouldn't slow down much for a long while still.

Next year should also be over 20 million unless they fuck up in some way, with the games they have announced and the rumored upcoming revision.

Looking at the trajectory of Xbox Series I think I’d prefer an Xbox Series vs PSP chart.
Especially considering one of the more famous threads on this forum.
I feel confident that the Xbox Series can take on the 3DS, but PSP will be a little tougher to conquer.

That said it’s pretty old for a comparison so you don’t have to take my request seriously.

I'd like to see both 3DS vs XS and PSP vs XS charts; personally I'm far from, confident that Sbox Series will outsell 3DS, I'm not yet convinced it'll outsell substantially more than Xbox One; it's tracking ahead so far but that doesn't mean it won't have weak legs, it's too early to say.

Xbox Series is keeping relatively close pace thus far in spite of supply constraints, but the real challenge starts once the early adopters all have one and we see how it's legs fare in the long term.

Switch should be close to ten million in front by the end of December. Amazing sales performer in North America.

Switch emerges from PS4's holiday season and is set to gain uninterrupted for the next 10 months. Won't be long now til it overtakes in North America. Japan has already fallen. Europe may be the only region where PS4 stays ahead.

It’s difficult to say what you meant to say, but I get you.
There’s still plenty of “Rest of world” regions where PlayStation is the indisputable leader.
Lots of smaller markets like New Zealand that love PlayStations that adds up to a big lead for Sony in those “Rest of World” countries.

I think you are talking to Curl-6's comment but I'm not 100% sure, but if this is in relation to the Switch's capabilities in winning the Rest of World region, it is plausible (and has a decent shot at occurring). PS4 sales have kind of halted, and the Switch sales are up a fair amount year over year (see paoerfulone's chart). Its fairly reasonable to say that the Switch will sell a couple more million this year to reach around 15 million in the rest of world.

The Switch would only have to sell around 5.5 million rest of life to beat the PS4's end total. (Note PS4 has to move 490K units in order for it to be this high, could be as low as 5.1 million)

The PS2's total is a different thing entirely though, and I don't know if any current console has the capabilities to topple it, though currently I would say switch is in the best position, though highly unlikely.

For small reference about everything said

Switch RoW total as of 6/19/21:       11.75 Million

Switch RoW sales in 2020:                5.144 Million

Switch RoW sales in 2020 (6/13/20): 1.748 Million

Switch Row sales in 2021 (6/12/21) : 1.934 Million

Assuming even a down year over year from here on out that would get the switch to 14.75 (Switch would have to be down about 12% through the rest of the year if I can do math)

At which point it would need 5.5-5.75 million (harder task as it starts from a lower number)

PS4 RoW Numbers: 20.01 Million