Except the API non-neutrality.

Only Apple applications are allowed to operate in the background. Element (Matrix chat application) actually had to disable its app showing up in the share context menu because the encryption method breaks when it was used.

I don’t know what features Apple photos or files have, but other apps wouldn’t be able to do background downloads (downloading files added to a folder by another device,) on-device photo digestion (apple photos classifies what is in your photos and what text is in them in the background for privacy reasons,) and similar things.

Edit: and yes I know that there’s a background refresh toggle, but it doesn’t work. It just straight up doesn’t work. That feature is entirely up to the OS when it wants to schedule that “background refresh”. In my experience it never does.

Edit 2: Also, only Apple storage integrates directly with the photos app and files app. And that only one comes preinstalled.

This is false. Apple OS’s contain numerous blockers and friction points that not only stop users from storing much of their data in other clouds, but prevent competitors from being able to develop them at all. Apple does this via elevated privileges/processes and proprietary API’s available ONLY to Apple’s own local apps and cloud servers, for example:

- If you backup your photos to iCloud, everything happens in the background with elevated priviliges and “just works”.

- If you backup your photos to ANY other provider, they run in a separate sandboxed process which doesn’t “just work” because the OS can kill it at any time, meaning users often need to leave 3rd party apps open for their photos to sync at all.

This is the same for every 2nd/3rd party service in comparison to Apple/iCloud across Apple OS’s. Nobody can develop a true competitor for anyone who purchased Apple hardware as Apple has access to a range of processes, services, and API’s which are not available to external developers. You can’t boot up an iphone and set Backblaze B2 or Amazon S3 as your authoritative cloud data or backup provider. You must use iCloud, or you get an inferior experience – not because of any technical limitation, but specifically because Apple designed non-Apple integrations to be inferior.

From the top of my head, you need to keep those apps open in the foreground if you want to sync your photos/files, while iCloud does it automatically on the background for you, showing that iCloud has an unfair advantage over the rest.

It’s also not just about photos. If you want to do automatic backup of your phone you can only do that with iCloud. Otherwise you have to connect your phone to a computer and do a manual backup with iTunes/Finder. Apple even killed off automatic local wifi backups by forcing you to enter your unlock code every time you trigger a backup via iTunes/Finder.