When Apple secured the OS from third party, they also purposefully closed the door on deeper third party integration to privilege their ecosystem.
macOS only being half as useful for Android users makes it harder to be the "best" for that swath of users. iPadOS being the only tablet form in the ecosystem will also distance other users etc. They just can't please everyone while locking them in a limited ecosystem.
When Apple secured the OS from third party, they also purposefully closed the door on deeper third party integration to privilege their ecosystem.
macOS only being half as useful for Android users makes it harder to be the "best" for that swath of users. iPadOS being the only tablet form in the ecosystem will also distance other users etc. They just can't please everyone while locking them in a limited ecosystem.