Well, I made my way through the stunningly scripted and acted horribleness and cruelty and brief humorous reprieves until the end. I’m glad to see you write about it with a focus on love as love’s absence is very much central to the plot. The personhood of their mother and her absence of love is also very significant in the formation of the Roy childrens’ evident insecure attachment... which is a consistent characteristic found in diagnosis of personality disorders and madness!
Shiv's decision is haunting; I didn't read it as being out of love for Tom but out of fear of being alone (with a child) and of seeing her brother win. After a lifetime of fighting for their father's love they're all incapable of trusting each other. The blow is softened by the fact that Kendall would have probably been a terrible CEO (how much worse than mattson/tom?), but love is at the center of the show's thesis like you said, and all the siblings failed