Of course, the digital revenue will keep tickling in but my point is regarding the revenue being made at the full price instead of mostly getting it from sales. It works for indies because they don't have the astronomical costs of development like a company like Square Enix, and similarly it also works for niche developers. But for Ni No Kuni 2 and other AAA games, the revenue is hardly noteworthy.
Keep in mind we are talking about an AAA JRPG here and when they are pulling in numbers of less than 100k, they don't seem impressive to me. The only reason Steam is getting them these days is thanks to the x86 nature of PS4. Otherwise I highly doubt we could have seen so many releases on PC, no matter how much of it was sold.
You point out the US sales for the JRPGs on PS4 but it is just a portion of the audience that plays these localized games. These numbers don't show us the full picture unlike SteamSpy. They also lack the digital sales for the particular games.
Just as an example,
Sword Art Online sold 450k worldwide and 70k of it was from US, and it was a digital only release on Vita, which is an extremely niche device getting a niche game. The game was also sold with an "Engrish" translation.
Danganronpa 1-2 were also released in two different games and sold a combined 200k in the West. This is a figure on a niche hardware and not something like PS4. This number was also LTD and not the debut month. Both games opened to <15k at retail in NPD FYI. So these games have legs and the same holds true for PS4. DQH, ToZ and other JRPGs won't stop selling their debut month. They will keep selling at retail and digital throughout their life.
I just looked at the newest indie Nuclear Throne and it has exceptional sales but do take note of its price as well.
Nuclear Throne ($11.99)
Owners: 167,595 ± 10,058
Now this is not a comparison but just an example that if a niche game is launched at an expensive price, it won't do much good on Steam. Clannad is one of them.
Clannad Visual Novel ($49.99)
Owners: 6,647 ± 2,003
So yeh, sales matter a lot for a game like Steam and hence if we just try to point towards user count, it doesn't paint the full picture at all. A lot of people just even buy some of the games on sale when they drop as low as 70-80% because it has become like an addiction for them. It doesn't mean they are interested in that particular genre.
I don't really see Ni No Kuni 2 doing well on Steam. It is entirely different compared to FFXIII, Neptunia and Undertale. It is the same case as Xbox One. I honestly think Ni No Kuni 2 if Ni No Kuni 2 is to be released on another console, it will be a Nintendo console because it fits the demographic.
Does a sale even matter for Undertale when it is being sold for $9.99?
Neptunia series is declining after each entry is released on PC. Might be due to abundance of them within a short span of time but in any case, each subsequent entry has only sold less than the original Neptunia.
Hyperdimension Neptunia Re;Birth1 ($29.99)
Owners: 199,247 ± 10,967
Hyperdimension Neptunia Re;Birth2 Sisters Generation ($29.99)
Owners: 90,523 ± 7,393
Hyperdimension Neptunia Re;Birth3 V Generation ($29.99)
Owners: 42,730 ± 5,080
To their credit, these are still pretty good numbers and they are REALLY good for a niche developer. But they won't work for an AAA game like Ni No Kuni, which was my point.