It is unclear if Apple decided to do this intentionally or not, but MacRumors reports that the change forced many developers to begin looking for a workaround. Attempting to access an app folder on iFunbox for instance brings a prompt saying "App Sandbox access is restricted by Apple to ones with iTunes File Sharing enabled since iOS 8.3”.
Currently users can only browse app directories that are iTunes File Sharing-enabled. Folks running Jailbroken devices will not experience any issues, however there has yet to be a Jailbreak for iOS 8.3. If you feel you've made a mistake by updating to iOS 8.3, downgrading is still possible, as Apple is still signing iOS 8.2, but not for long.