I respect your opinion but I am of (a minority on here) view that Xhaka is a lightening rod for disaffection with our team. He has been an important part of a team that has done so well this season (but dipped recently). That's not to excuse him for an anonymous performance on Wednesday - and there is hardly a member of the team that played well - but this may have been contributed to by the fact that he had been unwell previously.
I've said before that we can upgrade on the player, but we have come close to success with him as a mainstay of this team and I think that there are several others in it who could be subject to your comment about never achieving noteable success...including Jesus (as a striker at least).