You're underestimating the digital PS5 sales in Japan as well as the PC Japan sales while probably overestimating Chinese sales.
Maybe half was a bit hyperbolic, but my point stands that without knowing the splits, simply assuming that because PC was the lead system in the US that that determines anything on its own is a stretch.
I edited my post and added this:
It’s not just that PC was the lead system in the US. It’s that at one point, over 17% of the players were on PC at the same time. Unless you think 90% of the user base was logged in at once, PC would be the leading platform by a comfortable margin. Besides, it’s not like there are no Japanese PC players either.
The one thing that could offset this are the garbage user reviews that will surely hurt in the long run if they continue.
Edit: 1.30M on day and 1.38M on day 2. Even assuming they sold 5M on the first day, you’d be looking at over a quarter of all the players being on PC at once. Yeah, Japan with its 7M PS5s isn’t beating that. In the long run, if the shitfest on PC continues, then I could see PS pulling away. First week though? Data suggests PC is ahead.