I’m all for the “fake data” idea, but also: Apps should be required to gracefully handle the cases where users deny permission to access real data. I know last time I developed for iOS, it was Apple’s policy that apps cannot punish users or exit() the app in retaliation for them denying a permission. Apps must gracefully handle it and continue running. Also, and this was even longer ago, apps could not require users…
The guideline to be able to access apps without an account still exists, but the enforcing might have become lighter - or it's just the random fluctuations in review qualities we all know by now :)
https://developer.apple.com/app-store/review/guidelines/#dat...
(iv) Access [...] Where possible, provide alternative solutions for users who don’t grant consent. For example, if a user declines to share Location, offer the ability to manually enter an address.
(v) Account Sign-In: If your app doesn’t include significant account-based features, let people use it without a login [...]