There are first party developers here as well as 3rd party developers.
There are many different types of programmers here on this board (I've think I've identified most of the render guys, but there are others here too), and there are many types programmers involved in the production of the game.
For that example you have there for TLOUR - it wasn't free optimization. The game comes at a cost of triple buffer latency. Update code, render code, GPU - all of it operates at 16.6ms, but by the time you see the frame from the GPU, you are 2 full frames behind the update code. Not all games have that luxury, some games require instant snap response.
Hence, as per my previous post, first party exclusives can freely design over bottlenecks when it fits their purposes, but multiplatform games may not have that type of freedom. If PS4 had a processor that was 2x more powerful, it could have completed the update + render code in 16ms like a PC would have done (no additional optimization required), and than just be a single frame behind as the GPU does it work (this is the way most games are).
Lets be hypothetical here, what if it's possible that Xbox had just enough juice to bring the game from 24ms (as this is all CPU side) to 16ms due to the extra 1/2 available 7th core + additional 150 Mhz (per core), what would a multiplatform developer do then right? What if they need that controller response and the game cannot be designed the way TLOUR is, then compromises need to be made, because PS4 can't fit the game in 16ms.
I'm not here to discredit, or I think anyone here is discrediting the talent of first party developers - but it's unfair to say that they face exactly the same type of challenges or problems, or that the same solution can be applied in both situations equally.