Actually, I'm kinda skeptical about the whole "the OS is being developed in Japan" narrative.
Because when I look at the names attached to the announcements, details, etc of the recent firmware updates and stuff like ShareFactory, they're from :
Scott McCarthy,Director, Product Planning & Software Innovation, SCEA
Stuart Platt, Sr.Producer for SHAREFactory, SCEA
And we know all Remote Play features, integration and stuff comes from Gaikai, which are based in SCEA as well.
Whereas when SCEE is involved in the detail sharing of Firmware 2.0, it's not a dev that's sharing it, but rather marketing.
Isabelle Tomatis, European Marketing Director, SCEE.
Based off these details, I think it's far more likely that it's a combination of team members from SCEA and SCEJA working together on the OS, rather than just 'hurr Japan-only."
I say those two regions, because the way that Sony has updated and shared further details on these things shows that there's at least some amount of communication lag, because there are times when SCEA's infodump of new features are more detailed, yet there's times when SCEJA infodump are more detailed, which means both sides are presumably doing their own thing, both with knowledge of how the final features will play out in effect, thus sharing it out to marketing. Whereas SCEE are only recipients of the data, thus them only sharing out what SCEA themselves share, and are done by marketing instead of a product team.
I think Sony's approach towards their update of their firmware has a ton of room for improvement, but immediately criticising that it's because of the OS team being based entirely in Japan ( we don't even know this for sure ) is jumping the gun, imo. We know, unquestionably that the hardware team is based in Japan, but the software team, with a bit of due diligence, shows that there are people working on the software in US.