This narrative false. Recore, Quantum Break, Ryse, Sunset Overdrive were first party/second party titles, while on THE PS4 was mostly quiet for the first three years.
Sony studios hit the top gear, and you saw titles pushed out. Sony first party content was not great between the year 2013 and 2016.
Bloodbourne was released by a third/second party dev studio. Sony did not own the studio.
Ready at Dawn- Order 1886, same.
In reality Sony success depends on Guerilla games, Sucker Punch, and Naughty dog. Insomnaic will provide backup with Spiderman and other titles.
MS at this stage has 30 something owned studios and does not look the are stopping yet..
Sony got around 15+ owned studios, so the potential is massive for Xbox. Now is about delivering the content for its fanbase.