Exclusives don't matter as much anymore because the majority of console buyers are not playing them. The typical consoler player just play like 2-3 games a year and usually 2 of them are COD/FIFA. Back when gaming was more niche and the only people playing them were enthusiastic nerds you had to have an edge on the competition. The markets just not the same anymore, the main demographic is normies now and normies care about things like brand recognition over niche titles.
Nintendo is the exception to this thanks to the brand recognition
You know I find the lack of exclusives since last gen puzzling really, not just for playstation but also xbox. For a long time the ps4 was refered as a "bloodborne machine" becuase there weren't a lot of "worthwhile" exclusives, I am aware what makes a game worthwhile to a given consumer is subjective but even then there weren't a lot of exclusives compared to the previous two gens. I wonder if this is due to ballooning development costs "forcing" studios to go multiplat in hopes of selling more and recoup their losses, while first party studios or those contracted by sony/microsoft opt for very "safe" games to again sell enough.
There were a lot of factors to the lack of exclusives on PS4.
A large one was the departure of Insomniac from Sony in the first half of the PS4's life. Insomniac wanted independence, but after a bout of failing R&C spin-offs, the company had financial trouble and worked on projects with EA and later Microsoft. They wouldn't really become exclusive developers again till the R&C movie and more importantly Spider-Man.
David Jaffe also had a falling out with Sony and basically got kicked out of the industry after the blunders of Twisted Metal (2012) and Drawn to Death, so that likely halted Twisted and God of War.
Media Molecule was developing Tearaway for Vita till 2015, then decided to stack the workload with Dreams, which was an ambitious project that obviously took years to develop.
Naughty Dog just takes a long ass time to make games, plus the company seemed to undergo changes going into TLOU2.
Sucker Punch was also pretty much absent as their last game prior to Ghost of Tsushima was Infamous in 2014
A lot of the other studios just kind of died off
I think the PS4 is the ultimate showcase of how understated the impact of Sony's first party studios have on the company. Seriously, losing Insomniac and Sucker Punch for most of the lifespan was a massive L and it shows as Sony relied on those studios heavily during PS2 and 3. Jaffe was another massive loss.