I'm surprised Valve would support Sony's rather unpopular side in this issue. They should be encouraging the use of VPNs to bypass arbitrary and unfair geofencing.
IMHO what they actually think is "you're not worth our money to bother to go through all the bureaucratic processes", and it would be far less insulting if they just said so directly, but I guess this may have something to do with Japanese notions of politeness.
The best thing people could do these kinds of situations is "buying" their games on the closest torrent tracker. What I actually see is people spending money on VPNs and payment cards from far away places to still give them money. (I don't do either, fuck them.)
It's been a thing for years and non-US PC gamers have hated it just as long, as there is a lot of censoring in some countries. (Which you now have to either live with or pirate)
I think the point I made was still applicable though, despite VPN no longer being an option to purchase the game. The used method to evade the geo locking doesn't have an impact on the game costing different amounts depending on the area.