Any potential truth to the idea that these numbers are low (in part) because the PC requirements for the game are unusually high?
I'm not a PC or Steam guy, so I don't know. I'm just asking because it's an explanation I heard elsewhere, and I hadn't seen it mentioned here. I'm not "taking sides," just wondering.
Returnal - 6,691
Ratchet and clank rift apart - 8,757
Uncharted Legacy of thieves - 10,851
You had me scratching my head there for a moment, but I think the answer there is that each of those were late PC ports. Indy is different because it's day and date. Also, I believe that R&C sold below expectations (overall, not just on PC) - at least that was my understanding. I don't think Returnal did all that well, either. So you're comparing to games that didn't do very well.
Horizon zero dawn - 56,557
Days Gone - 27,450
God of War - 73,529
Spider-man had reports of selling 1.5M+ units, ccu peak 66,436
They're bigger numbers for sure but there's no extrapolation to be made here between the sales numbers and the CCU.
Those are all late ports, too. I don't think you can equate games that first come out on console exclusively and then are later ported to PC (with variable quality) to games that release day and date on PC. There are a lot of PC players who also own PS5. They would have played those games on PS5 when they came out, rather than wait for PC ports, so the potential audience would be smaller.
However, I do agree with your more general point - it's tricky business trying to correlate Steam CCU numbers to actual sales. It's all we've got, so people go nuts over them, but it's not even close a 1-to-1 correlation. For instance, I saw 4 different websites that attempt to estimate sales based on Steam numbers, and the estimates varied wildly, by a factor of 10 or more.