That has less to do with Sony and more to do with where audiences are. I'm talking about what Sony does with its studios or what they invest in.
They also dumped a bunch of their studios in NA and EU towards the end of last gen/start of this gen, didn't they?
I guess in 2012 they shut down 3 studios and then Evolution studios this year.
They still have:
Guerrilla Games - Killzone, Horizon Zero Dawn
Polyphony - Gran Turismo
Bend Studio - Days Gone
Foster City - Internal tools/dev support
Naughty Dog - UC4, The Last of Us Remastered, ICE Team
Northwest Studio - PSVR mini games
San Diego Studio - The Show
Santa Monica Studio - God of War and collaboration with a bunch of smaller teams on downloadable games/ports/PSVR stuff
Sucker Punch - Infamous
London Studio - SingStar, PSVR Worlds
Guerilla Cambridge - RIGS (PSVR)
Media Molecule - Tearaway, Dreams
PixelOpus - Entwined
SIE Japan - Bloodborne, Gravity Rush Remastered, Gravity Rush 2, The Last Guardian, The Tomorrow Children, The Playroom (PSVR), Deep Down
Honestly going through the studios you see that there's been a few big titles (UC4, Infamous, Killzone) a few more coming (Days Gone, Horizon Zero Dawn, God of War, Gran Turismo), a bunch of pseudo Indie stuff, a ton of tech support and probably 1/3 or more of the studios are working on PSVR at this point. That's probably why there feels like such a void from Sony's 1st parties, you have a couple of places like Sucker Punch that we don't know what they're doing but almost everyone else has transitioned to PSVR for better or worse.