I know that hiding bones hides keys on the Dopesheet view is often a cause of confusion when you are not familiar with it, however I think it could be a very useful feature if you were aware of this beforehand. Spine does not have a feature that allows you to lock keys or timelines, so it is possible to unintentionally select keys that you do not want to edit and break the animation, but by hiding bones, you can protect keys from accidental editing.
For example, if both the character and the VFX are in a single skeleton, if you want to edit the character's animation, you can hide the VFX's bones to protect their keys, and hide the character’s bones to protect their keys when you want to edit the VFX animation.
If a feature to lock the keys or timelines is added, it might be a good idea to separate the visibility relation of bones and keys.
