The definition of an "active" player is quite broad there.
And half of the 3DS' owners didn't play it at all last year ?
It's the existential crisis that dedicated devices tend to face in Japan. Much of their audience ages past them very quickly, and ends up in the gigantic mobile bucket as it fits their lifestyle and/or preferences much better.
That said, being king of children's software is still a sizable market, and that's on top of the other markets the 3DS managed to cobble together, leaving it with respectable numbers.
However, I think this helps paint the picture of why we see a continual downward slope in dedicated devices.
Considering how terrible the last game was, is that truly a fair assessment to make?
Products that are in tune with the market can recover pretty easily from bad entries. That they thought it was worth stopping altogether says a lot about where they felt the market was headed.
While I think that's true for Summon Night, which went a way for a long time before being brought back, I don't think Star Ocean ever really had a major shift.
It's always been a sort of "once a generation" series, and aside from the short gap between the first two games, the gaps have been fairly consistent. There were five years between 2 and 3, six years between 3 and 4, and seven years between 4 and 5. Those gaps have gotten slightly longer, but I'm not sure that amounts to much. They didn't really stop making it, so much as they just kept putting them out on the same, fairly slow, schedule.
Star Ocean 3 sold very well, but they still waited years to do a sequel. I think that this current status is more like business as usual for Star Ocean, even if the last game might have disappointed to some extent. I would guess that the logic for Square and for tri-ace is not so dissimilar to the logic for Star Ocean 4, or for Star Ocean 3. "Star Ocean usually does well, and it feels like it's about time for a new one".
It's possible that logic won't work out, and that Star Ocean 5 will wind up disappointing in sales compared to the last one. But I don't really think this feels any different from a "why now?" perspective than previous titles.
This is getting at what I meant with the studio moving on to other options though. They were putting out Valkyrie Profile with the same publisher at the time. Here, Square Enix wasn't hiring them to do other games in between entries that would help explain the gap.
They weren't even getting hired to do console games in general after Resonance of Fate and were doing a lot of work for hire. We're looking at a studio that was going no where and was offered a chance to try their hand at Star Ocean again as part of Square Enix reviving their mid-tier game business. It's that general revival however that I'm pretty skeptical about, since I don't think Wada was actually wrong from a business perspective when he shut off the output from pretty much everything but the Dragon Quest spin-offs.
That's not to say some of these things won't end up profitable, but I feel we're looking at a bunch of really low margin software that's basically there for prestige and fan relation purposes instead of the core of what's driving the business' return to health, and will not be surprised if we see a whole bunch of them have notable iteration over iteration drops.
Mind, I don't think Square Enix is alone in this type of decision making lately, and I fully understand why development teams that used to work on this kind of stuff would really like to do so again.