the app gets the ".notDetermined" authorizationStatus after a call to EKEventStore.authorizationStatus(for: .event).
The .notDetermined status indicates that the app hasn't requested calendar access to the user on that platform or if the app did, the user hasn't made a decision yet.
Your app should prompt the user for authorization as mentioned when the authorization status is notdetermined.
No, it does not and I do not understand why because it does on both iPhone and iPad.
What version of Xcode did you use to build and run your app? What version of macOS are you running your app on?
From TN3152: Migrating to the latest Calendar access levels
The iOS, macOS, and watchOS SDKs bundled in Xcode 15 deprecate the requestAccess(to:completion:) and requestAccess(to:) methods. If your app links against the iOS 17 SDK, macOS 14 SDK, or watchOS 10 SDK, calling these deprecated request methods doesn’t prompt the user for access and throws an error message.
See TN3153: Adopting API changes for EventKit in iOS 17, macOS 14, and watchOS 10 for more information.