I think there's something interesting there if you walk around the Last Dregs afterward. Now all the NPCs are talking to each other, allowing for both different dialog when we talk to them, and different idle speech bubble chat. (Apparently that Grebuloff that kept chanting for soup has had a concerning amount of it at this point!)
One of the NPCs we can talk to is the Nihilistic Nibirun (he's talking to a Karellian), who seems to be reflecting on the recent events around them; that they wanted to be part of something larger than themselves, but pursued perfect understanding (and much the same doomsaying attitude that the Ea had when we met them) rather than realizing that, hey, maybe they could just sit down and talk to people. Which, yeah, they weren't doing before--they mostly just hung around the edges of the places we were going and saying to themselves 'hm, yes, we're right, everything should die'. The scene in Elysion is the first time they've bothered actually HAVING a conversation and listening to someone other than themselves.
There's also one hanging out with the Emotional Grebuloff with a speech bubble line that really helps explain that whole 'without negatives there are no positives': "We once had cuisine..." That's actually a pretty great, simple example of what they're trying to get across: if people didn't need to eat food, we wouldn't have needed to come up with good food. Like the Ea from a different direction, the Nibirun escaped the need to eat... so they eventually forgot the joy of a good meal.
The tribe's an extension of the story of Ultima Thule, it's basically an ending for that particular zone. Which is a good move, that zone's one of the worst in the game in terms of its story being more 'central plot progression' than 'actual place with its own things going on', the tribe quest did a lot to make its population actual characters rather than plot-progressing cardboard cutouts. If I had to ding it for anything, it'd be for something that's true of a lot of the game: it's not going to win you over if you've already decided you don't like the story it wants to tell. If you didn't like Ultima Thule, it's not going to make you like Ultima Thule, but if you do like Ultima Thule it's absolutely top-notch; I actually think it might well be unseating the qitari as my favorite tribe quest, although I might need some time to chew on it.