Have you even played the game?

Sorry, but you must have really missed the point when you write something like this here.
The game is clearly about Spohia as "A Wife and Mother". There is a reason why the roles of Sophia as a wife and mother and not just Sophia is in the title. This alone gives the characters Dylan, Ellie and Liam more weight than any other characters, what you could also see well from the beginning. Just remember the scene in the introduction, with Dylan sitting on Sophia's legs in the car with a view of Ellie's cleavage, and the argument arising from it. Also, for one more example, Sam and Aiden in the story only makes sense because of Dylan being there. Without him, all this would go down to nothing.
Sorry, but I have to tell you that you are clearly wrong. Dylan and Ellie are clearly important enough to give them room for their own development. Even more, ideally this development should over time have an impact on Sophia, who is the mother of the two. That is what makes good storytelling. If AWAM is just an elaboration of events with Sophia, in which the other characters are empty shells, AWAM would be flat. A good story needs a few contemporary sidechraters and in AWAM this are clearly her core family. I don't know why this is a problem for you, but this is clearly how the game is set up.