I'd assume the reason for the stance they're taking is...
because Hydaelyn didn't want a "repeat" of the Zodiark business (That mind, she never actually allowed to even begin to pan out) with people becoming overly reliant upon gods.
Their purpose of essentially being the lynchpin that kept both the star and mankind from falling to ruin in the wake of the sundering is one I had long thought would be the case, but I'm mostly wondering if they still have some active role to play in either regard because existence is still in a fundamentally unnatural state of questionable stability.