Well yeah, a big reason Sony are pushing for GAAS is to be less reliant on 3P, but I think it might be shortsighted of them to think only GAAS can provide that independence from them. They have taken to GAAS because they are supposedly cheaper to make than AAA traditional games, and have more monetization options due to MTX.
But to me that's the easy way out. The preferred way would be to see how to keep investments prioritized to the bread-and-butter while cutting out excess costs. It's something Totoki talked about months ago, finding ways to reign in costs for AAA development without sacrificing on expectations. If the main costs for AAA games are things like content production, I dunno why SIE don't take studios like Firewalk and just put them on as support to other studios, specifically for making content and helping speed along programming & QA. Getting rid of consultancy groups like SBI would also help save money on production, potentially millions.
And then there's other things like making more AA traditional games; Astro Bot had a dev cycle of ~ 3 years and it's already looking to be a massive favorite and strong seller. I was always put off with the budget allocations between non-GAAS and GAAS that SIE shared at other fiscal meetings; some people want to say GAAS funding doesn't impact non-GAAS funding but that's pretending SIE's funding budgets are infinite. They aren't.
I dont think Sony is naive enough to think Gaas is the solution.
What they are doing, us expand their library. During the PS3 era, they had a lot of great mulitplayer games like Resistance, Killzone, MAG, Socom, Warhawk and Starhawk (as well racers, but there's still GT).
But last-gen, they were focused on singleplayer primarily and we've seen some mp studios close, like Zipper (Socom/MAG) and Icognito (Warhawk/Starhawk).
So rn they have almost only singleplayer and practically no multiplayer.
So the way I see it, is that they are going back to what they once were a more allround publisher with less reliance on 3rd party multiplayer.
It's an investment that they have to make now, to be less dependent going into next gen.
And to so that, they acquired new studios that were already working on projects, hence why we see titles like Concord, Marathon and whatever Fairgame$ is working on, rather than a new Socom or Warhawk.
(And GG and Insomniac are already working on multiple titles, so they have little room for a new Killzone or Resistance).