Part of the problem is with so many retcons in the comics some of those characters are depicted as anti-heroes rather than villains, similar to the attempt to retcon Thanos into one in Eternals by claiming, if indirectly, that his actions w were to stop civilisations going extinct when a Celestial is born and emerges from a planet, destroying it.

Galactus has been written in a very similar way before where the reason for him consuming worlds was to stop something inside of them hatching. Basically a galaxy wide pest controller.