The internal Spine.AnimationState
is updated in the Spine MonoBehaviour's (SkeletonGraphic, SkeletonAnimation) Update
method.
As with any MonoBehaviour, when you disable the MonoBehaviour, or disable the GameObject it's a component of, its Update is no longer called by Unity's game loop.
The only way it would still run is if you called Update manually.
In short, disabled SkeletonGraphics won't do anything by themselves.