Very debateable across the board there imo.
Lots of people weren’t impressed with Kolasnic early doors. And it is clear he actually is quite a limited football player.
Xhaka probably would be terrible for any top PL team imo. Not sure the league is for him. Or maybe he’s not reached the right stage in his career for it.
Iwobi you could actually argue the exact opposite.
Mustafi I know nothing about his time before, but meh.