Can you please describe the make-up of these families, the individuals raising the children in particular?
I can describe the family arrangements of the two people I'm most familiar with. One of them has three children, and she raised each all the way to adulthood. As far as I know, the children mainly lived with her, although they also spent a lot of time with their respective biological fathers. Sometimes their fathers also visited them at their mother's home.
The second one was raising her child with the biological father, but they divorced. I think she got custody, but, as in the above case, the child still spent a considerable amount of time with the father.
I don't know as much about the others except that they were or are raising their own children, and they dedicate as much of their lives and time to their children as you would expect any sane parent to do.
I think that would enrich the discussion very much.
I agree! I grew up in an extremely conservative society, so I found polyamory repulsive when I first knew it was even a thing (when I was a strict religious conservative). My thoughts about it have fundamentally changed since, mainly because of getting to know polyamorous people, hearing about their relationships, and realizing I had a lot of misconceptions about polyamory itself and polyamorous people.
It's definitely not for me, but I believe both I and non-monogamous people deserve to have the freedom to decide which relationship arrangement works best for us and also to be listened to instead of judged negatively solely due to our decisions in this regard.