The game folder found in here?
C:\Program Files\WindowsApps\
Yeah it's all encrypted and without taking ownership of the folder first you're quite locked out of it, there's some other stuff too such as how it does some encryption if you add a secondary location for these in the System Settings app and then network sharing being on for the User folder and if disabled it seems to interfere with the app system and it's ability to use the config files and such stored in the Packages folder and possibly more.
Just a bunch of overly protected nonsense really, certainly hasn't helped the games from being circumvented and Microsoft has also had a lot of apps as non-removable though RS5 here and the upcoming 19H1 version of Windows 10 for late March should relax it somewhat but the encryption stuff and requiring the user to forcibly take ownership of the folder first is probably not changing anytime soon.
(Doesn't break anything, not too much of interest in there either though and for adjustments the Windows PowerShell and the App commands seem simplest to remove/hide apps and alter things in here.)
EDIT: Oh and for taking ownership of stuff don't do it at random for those wanting to try it, Program Files, Program Data and Windows all use various stuff like system links breaking the entire install if you go about this carelessly, specific folders or subfolders only and even then you should be careful on how this is handled.
EDIT: And the game itself or app I suppose for non-games I believe is also using something like a virtual sandbox environment of sorts so accessing the file and folder stuff might not be the end of these issues. As if the UWP / Win10 store didn't have enough other problems and issues heh.
EDIT: Although I only know a very small part of how this entire thing is set up and works, mostly from complaints on e.g the file and folder encryption and problems and such stemming from these measures.