I agree with you. Moreover, at best, the FO moves he's upset with would be signing Mills and Pau. And the moment you start pointing fingers at other players saying "he shouldn't be making this much," the moment everyone in the locker room is going to hate you. Dude's a max player for the next eight years, don't about anyone else getting paid. I fundamentally don't believe Kawhi is upset about the roster right now. But if he is, when that roster still has HCA without him, him. The team shouldn't trade him, but he damned sure needs to recalibrate his thinking, because this would not go over well on any other team either.
However, I will say that a possible reason why Kawhi is upset would be that PATFO haven't committed to giving him a supermax extension due to his injury issues. Anyone who's objectively looking at this situation can see it's a big risk. It doesn't help that it almost certainly won't be insurable unless signed much later (like this time next year), after Kawhi has had a long stretch of games while healthy. The team simply can't afford for him to be in a Rose situation. It could literally cause the franchise to fall apart. Wanting to wait makes sense, but from Kawhi's perspective, if he feels like this injury is Popigenic, then of course he's going to have no willingness to give a discount. They'd be asking him to make like $30-40 Million less than he could make all because they didn't do the right things medically. I'd tell them to send me to a team that isn't trying to screw me over.
Of course, there are many different ways the above scenario can differ from reality. The biggest of which is that I doubt there was any malpractice going on with the SA doctors. And , I also doubt the Spurs have given Kawhi any indication they won't supermax him. Someone on RealGM did say that this type of injury can really fray a player's nerves, and I think we did hear something along these lines before. That may make him significantly more irritable or likely to vent his frustrations. This is moving to career-altering territory now, and even if it has nothing to do with anything the Spurs did or didn't do, Kawhi is still likely to lash out at them first (well after Zaza).