Arsenal fans, on the whole, would not be happy with that decision. However, the saga surrounding the newly-capped France international has become a sideshow at the Emirates.
Saliba has undoubted talent but if Arteta does not think he is the right player for his project, then that decision must be respected. Constant rumours about his future will also not be something that pleases Arteta.
Selling Saliba may not be the most popular decision in the short term but Arteta is all about getting the right characters. It is up to the Gunners boss to decide if he fits his ideal profile.
The alternative decision is to tell Saliba he is going nowhere. He still has two years remaining on his Arsenal contract and is still only young.