as a gameplay mechanic, the sages are kind of annoying and they get in the way and aren't there when you actually need them and share a button with the 'pick up items' button which gets chaotic super quickly, for the vibes, however, they are actually interesting to me.
BotW is spent alone, the champions are voices that echo through the halls of their tombs and at most, ghosts that appear for a minute or two before pushing Link away to fulfill their duty. But the sages actually fight by your side, both the real versions and their echoes walk by Links side and make the trek through the world feel less lonely. He has to interact with them to use their abilities; they're their own people with their own stories.
They act as decoys against enemies and make battle so much easier if you know how to work with them, and Link had to adapt to work with them. He's always fought alone and totk changes that in so many ways. He fights alongside the sages and with the monster-control crews and the various traveling Hyrulians defending themselves against the monsters that are everywhere.
Being alone in a post-apocalyptic wilderness was important in botw and it's important in totk that so many people are fighting back now. They're so much more involved with the story, people are looking for Zelda and Link after they went missing and the blood moon guy is getting captured by monster camps instead of just hanging out at a stable and dancing when the moon turns red. The world was never empty but in totk you can clearly tell how much the people have grown.
The champions gifts were a part of Link, they were given to him to use as his own, but the sages vows are avatars of the sages themselves. Link got the champions gifts because as spirits, they couldn't use them anymore, but the sages are alive and protective of Link. They're his friends, they've been his friends for years.
So I always have to have all the sages activated even if I think it's annoying when Yunobo wants to hurl himself at everything whenever I'm just trying to fly around. Those are Link's friends! They're Zelda's friends! They want to find out what happened to her too. They want to keep Link from throwing himself into increasingly dangerous situations, as much as they can while also having their own lives to deal with.
Also it's funny to see them wiggle around when they get grabbed by the gloom hands.
