What's the point with that quite lackluster story in Endwalker?

[Cutes]

It's funny, 'cause things like Dynamis are fairly common in anime and Japanese stories, and to a lesser extent western ones inspired by such. Think Undertale's "Determination", or "Spiral Power" from Gurren Lagann. The difference is that their respective "Believe in yourself!" magic systems were built into the setting from the beginning, while Dynamis is rather haphazardly thrown in.

I'm not sure if I want the writers to expand on Dynamis, ignore it going forward, or to dismiss it outright. Like, going "Actually Dynamis is completely unusable, and everyone who appears to use Dynamis was actually just using Aether". No matter what they do, I don't expect them to make it a worthwhile addition to the setting. But it's already poisoned the well, so to speak. You can try to take the poison out, but someone in the village still drank it and died.

Dynamis is a retcon for a lot of things, including things like the Limit Break mechanic and it’s place in the story. These things were previously attributed to the Echo and not really touched on too much (things like the Echo status effect say “breaking your limits in the way only a true Warrior of Light could”), but after we learn that the Echo itself is a property of having some fragment of the soul of a sundered Ancient it may seem weird. This becomes a bit more troublesome if you know the Echo in Japanese is called something entirely different: “the power to transcend”

One of the worst parts of the sundering is even if Hydaelyn thought the sundered races could be more in touch with dynamis, she didn’t have faith that they would be able to solve the problem as she made the escape moon as a final “out” from the Final Days. Ultimately this proves correct as not only do the Sundered fail to understand more about dynamis, they may understand even less as the concept of “Akasa” is limited to one culture and considered to be purely theoretical as it cannot be measured. She has no way of knowing this will come to be, but every sacrifice and loss of life becomes less justifiable when even Hydaelyn Herself doesn’t completely convince Herself that the Sundered will save the Star and it’s Reflections from the Final Days.