If there was awesome stuff worth remembering, you would at least remember something. From what I've heard, it's the backstory of – I don't even remember their names – and I wasn't particularly interested in them. So I guess I will leave it.
if I'm not mistaken, belters are poly because they looked being really close and personal in a ship, while Holden's family was more because legal issues and land rights. Holden's family wasn't a normal thing on earth, while Belters polycules were like the norm for Belters.