I think you are conflating lack of ability with lack of professionalism. Patrick Vieira is the jonit Arsena record holder for number of yellow cards in one season. He also holds the joint EPL recors for red cards; flirted a number of times with other clubs and allegedly threatened to break Roy Keane's leg. Would you argue that he was unprofessional. Most people certainly wouldn't.
And this is my issue with the Xhaka hate. Most of it stems from the fact that he is in many fans eyes not good enough. In many cases, it is his lack of pace - and desperate attempts to make up for being bested by opposition players - that has led to his bookings. It could be argued that he cares too much, and certainly that he lacks the right temperament to deal with pressure situations, but I don't think this is most accurately described as a lack of professionalism.
By all accounts, the player is one of the hardest training players we have; a 'go to' player in terms of leadership of other players; and generally speaking his injury record has been astonishing - that perhaps speaks to a desire to be in the picth as well as a physical robustness. He has accepted being played out of position (eg LB) without complaint; never bleats to the press; continued to put maximum effort in after being stripped of the captaincy (admittedly after an unprofessional reaction to the crowd); knuckled down after attemopts to offload him to Roma during the Summer, and while he just isn't an 8/10 player (not his fault) can generally be relied upon to give 7/10 performances week in week out.
Given Arteta's treatment of players who don't have the right attitude - including players the club has had to pay to leave - do you really think he doesn't show professionalism to the manager?
I don't particularly want to be a Xhaka cheerleader but I find the hate of this player tiresome. As matters stand he is an integral part of a team that is perfoming well.