I get where you are coming from but there are a number of things which go against your argument imo.
Does he not get on with Pep , and is his attitude wrong ? It appears that Pep has been frustrated with his performances on the pitch , does that carry through into training etc, does it cause issues within the squad etc. Does he have an over-inflated oipinion of himself, and believe that he is already " one of the best players in the world " , if that is the case I can't imagine it going down well with our management team/
He clearly is very talented and capable of some excellent performances, but equally he can also be quite ordinary when not on his game.
Clearly it is all about opinions , but if Pep is frustrated with him and it is due to attitude or application, then getting the best price possible and moving on seems like the best option .
And before I am accused of being a hater, if Sane really wanted to stay and would commit to the club , rather than having to be tempted simply because of the contract offer , then I would be delighted.
However, I am firmly of the opinion that he is off asap.