That comparison should say it all. It really depends on the longevity of the console. I think we can all agree the GameCube did terribly in Japan (4M), yet it was slightly ahead of both the PS3 & PS4 in the same timeframe. The PS3 hit its numbers (~10M) because it consistently sold well over a large number of years. I don't think the PS4 will even be Sony's main console as long as the PS3 was.
Sure if it actually hits 10M somehow, I'd say the PS4 did decently given the current climate and that nearly everyone's expectations are lower, but it's still a huge contraction of the general console market in JP.
We should make some considerations :
GC - it didn't started bad at all, it was challenging with a system called PS2, the problem is Nintendo really dropped the ball fast, let's say after only 3 years, so an overall comparison can't be made in my opinion, but just as a 2-2,5 years
PS3 - opposite from GC, it lasted around ten years and most of the top seller games were released during 2010-2011, four years after the launch.
Still opposite from GC, PS3 started terrible, it was challenging a mass-market system called Wii with an astronomical price (things turned good when Sony first dropped the price, secondly introduced the Slim model)
So while GC can be used as "starting" comparison, PS3 can be used for an "overall" comparison.
I do not think PS4 will last less than 6-7 years, it's not a nintendo system, so reaching 10mln would be, considering the actual home market, a very good result.
Of course actually we can't say that result can/could be achieavable, but with Sony shifting all their own efforts towards PS4 and being PS4 probably the only good home system (I don't have faith in NX home version, Nintendo should focus on the only thing nowadays they can do : handhelds) I would say that 10mln should be a target for them.
This is my analysis, and not mixing apples with oranges as comparing PS4 with 3DS (how long before everyone gets tired about comparing an handheld with a home?)