Sony always has variety but if you mean games like TLoU, Uncharted and GoW then it's true that most of their biggest/most popular games are 'sad dad' games.
Sony's other games either aren't as good/appealing or Playstation doesn't attract a big enough audience for those types of games.
Nov 2016 - NES outsells PS1 (JP)
Don't Play Stationary 4 ever. Switch!