Mount’s daughter and first child was born shortly before production of season two. He limited his availability to be with his child. As a Canadian, living in a country that has parental benefits and encourages dads to use them, I can get behind that.
Mount has said that he disliked the experience of being on a soundstage 24 or more hours a day an prefers location shooting when possible. Due to COVID the timing of production shifted and some of the episodes (e.g., the fourth) that were supposed to have significant outdoor location shooting moved into the AR wall stage. So, some of Mount’s other appearances may have been pulled back.
Two things are an issue -