To enforce run time permissions it is recommended to use GetSafeDirDefaultExternal if you do not want to use DirInternal, but is it really safe? I can still use a file manager, drill down to Android/Data/Pakagename/files/myfolder and do whatever I want to do with the files in myfolder, such as modify, delete, rename, etc. Wouldn’t that render the store not safe? Where does its safety come into play if there is such thing as safe?
If something is labeled 'Safe', it must be protecting you from some harm. What is the harm that it is shielding me from. Where is the safety here if anybody can have access to the files in the folder, delete or destroy their content.
Safe in this case means that it is safe for you to use this folder. Unlike File.DirDefaultExternal which requires a permission which is considered a dangerous permission.