At first, these Eclipse Seed species could be said to be benefiting from Stardust, because they are able to evolve into stronger, more powerful versions of themselves. However, when the level of Stardust in the body exceeds a certain threshold, a backlash begins.
Stardust's sole purpose is to keep spreading, and it does not benefit from being too highly concentrated in any particular life form. After a certain point, Stardust will therefore begin to consume the infected lifeform from the inside out, eating away at the host, and spraying tiny Stardust particles into the surrounding air like a plant dispersing its seed.
This is what has happened to many of the Mutant Wolves who roam the wilderness - mangy and worn down, with little to no remaining fur.