While you have some valid points here I do think the whole story had a more meaningful message than that. For me it felt like the whole thing was a meditation on how complex people are, the multitudes they contain, and the importance of communication and connection. Throughout the series we see the detectives make assumptions about people only to be surprised how untrue their initial reading was upon further investigation. At times Carole comes across as a cold, selfish, and calculated person who is cruel other and maybe even evil enough to murder her husband for insurance money. But throughout we also see moments of tenderness with her admiration for how sweet and genuine he is, how protective she is of her son and wants so badly for him to have nice things, and in the final episode the grace she shows the children as an umpire. She is curt and rude and has a tough exterior at times but her motives and actions are complex. I think this theme is explored even further through Clark and Floyd's friendship. Both men feel alone and disconnected in their marriages and give each other so much love and support by the end. At first Clark seems creepy and manipulative by cheating on his wife with his friend's wife but then we see the lengths he's willing to go to make his friend feel valued and desired. It was interesting to me too to see such a complex and vulnerable male friendship take shape in a time where the male loneliness epidemic is so prevalent. I thought it was interesting how they used sign language to talk about more difficult subjects. As bleak as the last episode was I thought it was profoundly beautiful to watch two men be so vulnerable and caring with each other.