So was the PS4, so what? You PC extremist can't even come to terms that porting PlayStation exclusives to PC has consequences, it's incompletely absurd to think otherwise.
It's implied in you discourse that Nintendo could release all their games on Steam today an that would only benefit them and have no impact on the sales of their consoles. Wake up.
Xbox start porting their games to PC, it is followed by negative momentum and the eventual death of the console.
PlayStation start porting their games to PC, PS5 starts to track bellow the PS4 and misses an estimate of sales by over 4m units.