Time to Triangle has nothing to do with SCE's poor leadership with first party efforts.
PS4 might be doing incredibly well, but that doesn't excuse SCE's malady of poor decisions. As a huge fan of PS3's first party efforts - this is aggravating, but it makes sense. As market leaders- WWS took this generation as an opportunity to reboot studios, cut fat, and try and catapult studios stuck in purgatory into something much greater.
However- I agree with some of the posters above- SCE's First Party/Second Party work this generation is a blazing glory of mediocore. The timeline of mishaps speaks for itself:
1. At launch Knack and Killzone were critically panned. Despite good intentions of having first party software at launch, both games are more or less the butt end of jokes.
2. Sony Santa Monica's new IP was cancelled and left a huge gap in the Fall release schedule last year.
3. InFamous Second Son and Little Big Planet 3 are the weakest iterations in their respective franchises.
4. The Order: 1886 backfired into an oblivion I haven't seen for quite some time.
5. Drive Club (while incredible in it's current form) launched without the ability to function as advertised.
6. Naughty Dog trashed and rebooted an entire Uncharted game leaving another massive release schedule omission.
Bloodborne and Until Dawn are really the two shining examples of "we did it right." 2016 looks like an incredible year, but they really need to step their game up because PS4's WWS is a shell of what PS3 offered.
Looking at other games the difference seems to be either broken games shoved out to meet deadlines (AC Unity, MCC and so on) or they're rough around the edges as launch or early release window titles (Dead Rising 3, Forza 5 plus some f the games you mentioned) or they take time or get delayed.
Bottom line on consoles producing a well optimised big budget game seems to have gotten much harder (perhaps the number of platforms contributes too) and TBH all things considered I'd rather Sonys approach (be bold and cancel games not working out, push back games to allow them to be properly polished, etc) than the more MS and Western dev approach of shoving them out regardless then if they do find an audience dropping 5GB plus patches in an effort to fix things post release.
Myself I think the competitive need to release often and hit announced dates is taking a heavy tool this gen. Nobody (not even Nintendo really) has been cranking out terrific games with high production values quickly.
I see no major error or outlier for Sony vs anyone else. Not being defensive just noting it's an industry wide issue so far as I can see just with different studios taking different approaches.
Couple of points to your list. While exclusive The Order was a RAD game and ironically was one of the few big titles to actually ship very polished technically. It wasn't good but that's clearly on RAD not Sony so far as I can see as they merely published it and gave general backing to RAD.
And poor old Driceclub was clearly a one in s million outlier. They delayed it as d prefer to polish it, it launched apparently in decent shape technically but with the kind of bug in the server code design that's a major horror story. I always want to cut it some slack as while it was deserving of criticism unlike obviously broken games rushed out it was instead clearly the victim of the rare code issue that passes internal tests and only surfaces in the wild.
Not that there's not an issue of sorts in principle: but it seems to be more about development process for AAA games with increasing complexity and content vs tighter schedule and increasing external business demands (game has to be ready for Christmas vs when would game actually be reasdy).
I can only assume that if, for example, most similar MS titles had been delayed to be properly completed and bug free the number of exclusives would look similarly weak.
From another perspective I'm not sure it matters that much competitively at market anyway. Sales make it clear the big multiplatfofm games are way more important for driving console sales than exclusives anyway.