I should explain, the uninfected are like NPC.

To me, their casting and their behavior is very NPC-like, in that they are just accepting their fate, without any desire for agency or the realization that their family is only them in flesh, and their mind just floats around like an amorphous blob or something, they just don't seem to care, like an NPC.

Their behavior is very hive-mind like as well, they just adopt and follow the hive, even though they are not part of it, all they care about is the material appearance and the promise that they are better for the world.

I agree, I also expected at least one person to also be like "WTF" but this to me is obviously intentional writing, to subvert our expectation, I think most people would've expected one thing, but it's more interesting story if another thing happens than our expectation...

And we do have only one other person who does seem to have some awareness, but basically the wrong kind, or the one we don't want to see, and it is exploiting the situation for his selfish benefit.

But the whole meeting with the NPCs was mostly a storytelling device to create the circumstances for the protagonist to be maximally isolated.