So the Ozil thing is a bit complex. His failings are partially his fault and partially due to Wenger.
On the one hand, I watch guys like KDB and even [cough] Eriksen, and feel that they put in much more on a weekly basis. KDB has gone significantly past Ozil, regardless of the talent around him, and a lot of it is his application; just being at the heart of things at all times. I don't think Ozil gives enough and I can comfortably say that because I have actually seen him playing about half a season of football when he did give a shit and it was sublime. He was a top 20 footballer when he did. So that's on him.
And then there is the other part: Wenger. For the last ten years, this idiot has decided that it is sufficient to only ever have two superstars on your team, while serious title contenders amass a minimum of four or five to get going. Ozil has never been given the array of talent to aim at and to feed him properly. This has always annoyed me. Even today, the minute we brought Ozil on, we took off the player he would (on paper) best link up with in Lacazette. We never brought on the only other player in Wilshere who is technically anywhere near his level so we could get any semblance of link-up play. We were so broken today because we have a team that's about as technical as a pack of cart mules. So Wenger multiplies Ozil's own limitations by creating an environment where he is never going to thrive.
You put those two things together, and the player is better of leaving. Maybe to help rebuild Bayern. But he's not going anywhere under Wenger