I don't quite understand what PSG are doing. Pogba-Neymar-Mbappe-Icardi/CR7 would never work, cause at least 3 of those players must do some defensive/dirty work. Even someone like Kante does not compensate for putting Pogba in a 2 man midfield. You probably need 2 pure DM's next to him, but then he will get choked by the opposition as the only forward thinking mid.
Granted PSG are FFP immune, especially now that they didn't go for the Super League, that's still enough to upset any dressing room/budget. Especially if those players are not doing something like 80+% game time each.