If you accidentally click the scene eye in Hierarchy, it will flood your entire list with a visibility change. However if you click it again, to undo that, it does nothing at all, forcing you to go through every single element and set visibility manually to fix it.
In big game hierarchies it’s some kind of foul joke.
Please fix it, waited months. I don’t like to moan at all, it wounds me more than you, but enough … is enough.
Hi! This is fixed (again) internally, on it’s way out for 19.1/2/3. Very sorry for the trouble! As a temp helper, you can use assign a shortcut for “Show All” in the Shortcuts Manager > Scene Visibility.