I think it's difficult to portray the RAD situation as a mistake. Sony's relationship with them was never defined by their ability to make VR games, which is something RAD only pivoted to after their relationship with Sony. But I don't disagree that having another VR studio would've been good for them.
Bluepoint and Arrowhead seem viable, more so the former. But From Software is not happening unless Kadokawa want out of the gaming industry. I see no other reason why they would let go of an asset as important as FS.
I do think that Deviation and Haven studio are possible studios that Sony is eyeing. But I imagine that first depends entirely on how their debut games perform + the working relationship established making said games.
My logic with FROM is that Kadokawa is not really in the gaming business.....its pretty much just FROM by revenue and they haven't made any clear moves of expanding. And their gaming business doesn't add much to their bottom line either.
Imo, and I think FROM kinda knows this, FROM is a studio that could become a leader in the RPG genre, up there with Bethesda and CDPR, however they are often quite behind in tech and it seems they haven't grown as quickly as they should be.
Combine that with the variability of publisher fishing, IP ownership, I think FROM with be a whole different beast under a AAA gaming publisher.