The botched comical farce ending that he makes fun of in the book becoming the movie ending was offensive... I loved so much of the pieces but talk about a slap in the face.
Also, removing the detail of Pathfinder failure so you have months of mental health issues... Damon did spectacular at emoting the strain in the moment he regains contact with the crew, but it felt disjointed without the context of zero contact and the desperation.
Many of the actors were amazing, but Ridley screwed up bad.