Sony's first party support has been at Nintendo levels for the past few years. Their third party support has standard AAA games, but also gets all these awesome Japanese developed games that often fail to show up on other platforms *cough* XB1 *cough*. Then add in PSVR, which is a damned good accessory, and has two amazing games built just for it. And PS5 won't be coming out in 2019, due to no Sony at E3 this year. So PS4 still has a good two to three more years in it. PS4 should sell 120 million units lifetime. If it doesn't something is wrong with the gaming world.
NES, SNES, Genesis, PS1, PS2, GBA, GameCube, Wii, PS3,
Wii -U, PS4, Switch, and PC.