You can edit this auto optimization button via configuration settings. Options could be "distance from camera"[x tiles] meaning that if the camera, for ex, 2 tiles away from an object, entity or another tile, auto hide everything.
Turn [on/off] line of sight meaning that if the camera is directly looking at a wall, should the things behind the wall still be rendered regardless of the distance?.
Another option could be Exception groups[v Dropdown menu of created object groups v] meaning that the specified groups will always be rendered.