It's weird. It's taking a little longer than I anticipated for Splatoon 2 to reach 10 million, even with the updates becoming less frequent after the last Splatfest. Still, I think Japan will more than hold its weight just enough for the game to reach 10 million. It would be an incredible achievement for the game, a first party third person arena shooter with a focus in online-multiplayer that took over Japan akin to Dragon Quest, Pokemon, 2D Mario, and Monster Hunter.
If only! It's just so close!