Ozil’s relationship is with the fans.
The fans don’t care that other people might earn more money than him.
As you have noted, they pay his wages. (I say “them” as I’ve long since stopped going to games or subscribing to sports channels so I’m not contributing much if at all).
Some of them make sacrifices to do so.
To a lot of fans £1,000 a year or more - plus all the travel, etc - is a significant amount of money.
I don’t know or care if Bill Gates has taken a pay cut (does he even take a salary now?)
If he was earning millions and being asked to and refused then I’d probably think he was being a dick too, but pointing at other people and saying “well what about them” is the definition of whataboutism.
It’s not valid. You can’t excuse person A’s behaviour by pointing out that person B is also behaving badly or even worse.
If your point is why is Ozil being particularly singled out, well that’s a fair question but I guess it’s because he’s been a target for fan criticism for a while and is our higher earner. It makes a better headline than if it was someone less high profile.
So I guess I vaguely agree that singling him out is unfair.
But I also think he’s being a dick if he is refusing to take a 15% pay cut. Which doesn’t mean other people aren’t also being dicks.