What else did you expect from Manchester United? They can’t keep him to be their third choice keeper because it is disrespectful for him because he was the number one keeper for Manchester United, so is better to let him leave to any place that he will have playing time than staying in Manchester United bench for the rest of the season.
Onana should just accept this offer because Manchester United management and Amorim don’t value him anymore, and Manchester United fans are not happy seeing him in their squad because any opportunity they gave him, he always put them into trouble just as he did in the against Grimsby In the Carabao cup as Manchester United get eliminated.
However, he is a good goalkeeper based on history and he can do well in the Turkish league.
In as much as am feeling bad that he is about leaving the club, but he has no one to blame because his destiny was in his hands but he threw it away by his terrible performance in front of goal at Manchester united, the best thing he can do for himself is to just accept this offer and move on because playing as a third choice goalkeeper at Manchester united will be too shameful to him as a player and a person, so it would be understandable if he accept this offer and move on.