As I already explained, this leaves a files you've opened 'just to look at' vulnerable to corruption by cats, errant keystrokes etc.I just have to point out that the system does *not* insist that you save changes. It just insists that you explicitly undo the changes (by going to the last saved version, two clicks)
You cannot know to explictly undo the changes that you do not know happened, and the OS will silently save those changes.
That's a new path to file corruption brought on by the new autosave/versions/file locking system. Admittedly, versions will let you get the original back, if you notice the problem before moving a file to a different drive, duplicating etc., but that's more a matter of chance than certainty.