In all fairness, it is a damned if they do, damned if they don't thing. There are very legitimate reasons to lock down the OS. Leaving it wide open is just asking for problems. Encouraging users to have regular user accounts and protecting system files and folders from being tampered with puts limitations on what malware or bad programming can do. All modern OSs protect these as well. It is up to all developers to keep current with modern best practices.
In this case, the fix, not just the workaround, is fairly simple and should be addressed with the next version/patch. The other point is that for something as complex as this game (and these kind of games have always been and always will be more complex than the average adventure game) it can be extremely hard to catch all of the bugs at first go. Think of how buggy the QfG games were. This particular bug would have absolutely been caught if some of the beta testers had been running Windows with defaults, i.e. regular user with UAC on.