I don't disagree but it's kind it's definitely redundant to have two post-apocalypse zombie-esque Its (The Last of Us and Days Gone) which
I said way back before launch. Much like it was a redundant to have two racing sim franchises (Gran Turismo and DriveClub).
I know these are both instances of different takes of a genre but your halving your diversity of your IP, especially when you consider the other post-apocalypse IP from Sony first party studios like Horizon Zero Dawn and post-apocalypse survival is already a massively matured genre what with Dying Light and the resurgence of modern Resident Evil.
I would've agreed with this years ago when development cycles were much shorter, but not in this day and age. I think there's plenty of room for alternation between releases from each franchise, with a 2-3 year gap between releases amounting to 4-6 year development cycles per game. Heck, that might even be enough to avoid crunch (kidding! Unfortunately...)
So yeah, having them release too close together would be a mistake, as would be making them too alike.
On the former point, I think it would be fine if Sony are just focussing on launching The Last of Us at the same sort of time as the TV show, with a new Days Gone to follow a couple of years later.
And on the latter point, I think the cutscene heavy nature of Days Gone is one of its weaker elements, one that could be almost completely done away with as both a point of differentiation and a means of keeping the budget low.
The gameplay of Days Gone was strong. The story, less so. Serviceable, with some effective subversion of expectations, but nowhere near the calibre of TLoU games. Less cutscenes, more RPG style character interactions is the right move IMO.
As much as I like the strong cinematic, narrative focus of Sony's 1st party games, they need some small quantity to scratch other itches. A light narrative (or, at least, light on cutscenes) open world game with a focus on emergent gameplay would be a very welcome string to Sony's bow. Integrate multiplayer modes into that with purchasable cosmetics and they've got a solid, fun, profitable game IMO.
And then, integrate Warhawks somehow.