if you only had a PS4, or you Only had an Xbox One there's a lot of games you wouldn't be able to play either. what's your point?
not everyone is like you and insist's on owning only one gaming system. in fact the majority of people own at least 2 consoles. and generally, it's not a PS4 and an Xbox One they own. it's a PS4 and a Switch, or it's an Xbox One and a Switch. it's extremely rare to hear someone say they own a PS4 and an Xbox One, and the people that do usually own both PS4 and Xbox One usually end up owning all 3 of consoles anyway.
why are you so intent on acting like people will only ever own and play on one system ever?
Why wouldn't I strongly consider a Nintendo system if it got 90+% of all the games like the PS4 or Xbox or PC?
name me all of these amazing Xbox One games that you can't play on PS4.
Halo, Gears, Forza and Fable? wow! such a larger library you've gotten yourself there. 90% of the Xbox library is exactly the same shit as what's already on PS4. i'm curious why if you're going to buy another system, you'd buy one that mostly has the exact same stuff you already have on PS4?
say what you want about Nintendo games, but at least there is a large amount of exclusive stuff on there that you can't get anywhere else.