Thank you for your support! I'm leaning towards the conclusion that the issue might not be related to thread contention. I'll take a closer look into the aspects you mentioned and investigate further.

** correct - make default value rather then optional.

Thank you for your comment! I didn't know the app container remains after deletion, which could hinder fixing SwiftData bugs through reinstallation.(like iOS) Ideally, it should be bug-free from the start, but having a straightforward method to fully remove it upon deletion would also be beneficial.

I've also read this thread: https://forums.developer.apple.com/forums/thread/76891 (answered 6 year before) but it seems there no way to make "clear out" swiftdata when app deletion in macOS programmatically.

Thank you. Is there a reason why this method doesn’t work on macOS 14.4.1 or 14.4? It works fine on later versions, but on these specific versions, it doesn’t add automatically, and I have to manually press the ‘+’ button to add it.

thanks