I don't know if I misunderstood what you meant, but there was the couple during the gondola quest. The Elezen man tells us even though he died and the woman he loved forgot who he was, she never married anyone else, and felt a sense of loss. It's implied that she remembers him now, and we see them happy after he proposes to her on the bridge.
That is the only quest in Living Memory that I remember of that tries to dwelve a just little deeper in how they work - how it's very rare to have meaningful encounters there (even though Namikka died like 10 minutes ago and we meet her there so Wuk Lamat could have another moment), how the system is collapsing and not even 10% of all of the stored memories are present right now (even though Namikka...), and how he's been waiting for years to have this chance.
From the start with the Elezen, to the gondola musings of G'raha, this quest feels a bit different in how the rest of Living Memory was written. It makes you think about the system from the perspective of the Endless, and G'raha makes you think about our own feelings, if we would do the same in Sphene's place, and how we would feel as an Endless. It's like there was the intention to make us think about it and have a non black-or-white perspective...
...then immediately after, we go back to "let's meet them! But they're not really alive, so let's also kill them. They need souls and stuff, that's not sustainable. No, you don't get to think about it. Look, Wuk Lamat is happy playing with the Endless children!"
Before Living Memory, the game already talked about how it defined life, and Ultima Thule, and even some of the tempered plotline in 5.4, is proof that what makes us treat beings as alive is not just the simple combination of "souls and memories", it's consciousness, the sense of self. People in Living Memory can form new memories, can interact with the world (both inside AND outside) feel alive and have their own identities. These writers had a lot of trouble throught the entire MSQ to try to explain more midly difficult concepts, so they didn't even try, and tried to take attention away by deciding how we should feel about it depending on the scene, instead. "You should care about the endless when speaking with 0/3 locals, and during our tearjerker moments. But then don't care too much when we turn them off, they were just AI chatbots!)