[momonae]

Originally Posted by Triple_R

A few episodes back, we saw that almost everybody in this school was paired off with a same-sex lover. Mamoru was the only exception I noticed, and that's because of how massively committed he is to Maria.

It's not really that suddenly "almost everybody in this school was paired off with a same-sex lover". It's the anime's fault if many people are misguided into thinking that way or adolescent homosexuality is encouraged by the authorities.

Now, you have an official procedure by which each person is paired off with someone of the opposite sex. Why is this kept until adulthood? Why the sudden, widespread change from homosexual relationships to heterosexual relationships?

If you mean 当番委員の振り分け by "an officail procedure", it's not "an official procedure by which each person is paired off with someone of the opposite sex" but "virtually official event in which they confess their love."

We know this is a tightly controlled society. So I think that the implications, at this point, are clear.

Yes, many things are supposed to be controlled, but what makes you think "Adolescents in this society are expected to have a same-sex lover or lovers" and "Relationships are generally monogamous"?
I think there is none but it's difficult to explain why when you can't quote what is written in the novel. The anime is so far very faithful to the novel, only it seems that it doesn't have enough budget and episodes, and maybe in some respects lacks skills needed in anime adaptation. And I think it will remain to be faithful until the end supposing the novel is rather a serious SF and it's aired on TV asahi, so I don't think they have brought in the anime's original settings either.

Honestly, what you're writing here makes no sense at all to me.

Yes, I can get how a fictional world can be interesting/fascinating in and of itself, and that certainly is the case with Shin Sekai Yori. But there's no way I could care about such a world unless I cared about at least some of the characters in it.

I mean even in a supposedly objectively written story like biography, I often sense the writer's favoritism toward the characters within so you can often empathize with them or like or dislike them. But I largely didn't sense that in Shin Sekai-yori, maybe it's the author's style of storytelling, but I don't know, my speculation on that would become a spoiler.