[General Questions and Answers] TheMystic:
This app is useful for managing cloud storage as well as the membership. It allows you to also see what apps have been backed up, even though there is no control over it, i.e. user can't choose what to backup.

I just checked the details under System Settings, and here's what I see:

View attachment 5649837

But on Google One app, the details are quite different:

View attachment 5649839

When you look at the size of the backup, 88 MB is just too small. Moreover, I have over well over 200 apps downloaded and installed (Google Play Store shows 294, which includes preinstalled apps). What about the backup for the remaining apps?

If I delete all my backups on my iPhone and do a fresh backup, it will be well over 1 GB (no user files included, just the app data).

Very few apps are included here. For example, the same file manager app which you confirmed allows app data to be backed up, see the size of the backup:

View attachment 5649841

And see the size of backup of other file managers which have much fewer user configurations:

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9 KB is just too small, and I'm sure this app will need to set up again if restored from a Google backup.

Quite strange that you are defending a feature that you don't use yourself. There is a lot of manual work involved in setting up a device after a factory reset. On Android, app permissions are scattered in 3 different places:

1. App Info (ideally, every single permission must show up here)

2. Permissions Manager

3. Special Access

One has to configure all those for each app, and doing that for 100 apps or more is quite a lot of work.

On iPhone, none of that is required. Besides, iPhone also allow for 'offloading' apps, which allows you to uninstall an app (to save space or for any other reason) while keeping the app specific configurations saved on the device/ iCloud. So next time you install the same app, you'll find that it is already setup. Can you do that on Android? We are not talking about ADB backups or those made by Titanium Backup/ Migrate or others.

Removing permissions for unused apps is a good security feature. But here the issue is for all apps. A restore after factory reset doesn't restore any of the permissions set for the app. They have to be redone manually, e.g. internet access, battery optimization, wifi control, modify system settings, etc.

This points to another major flaw with Android. An app should only have access to what it needs for core functionality. Where critical information is involved, such as login credentials, Android must provide something similar to Apple's 'Keychain', that will store everything in encrypted form within Android's security framework.

And what gets included in backups should be purely user configurations. For file managers, that would be all remote connections, app settings, etc. For launchers, that would be wallpaper, homescreen layout, etc. Those that the user has specifically provided. It shouldn't include information that the app itself has collected over time or cached in its directories.

On iPhone, most things have to be strictly done in a very specific way, and may be that's why iPhone is able to provide features like 'offloading apps' as well as able to restore backups without any manual intervention whatsoever. On Android, developers seem to have a free hand in designing their apps the way they want, making it difficult to provide a reliable way to offer features like the ones above.

In your example, the failure points to the fact that there was no verification of device ID. If that was implemented properly, the backups wouldn't have worked on another device because of a device ID mismatch.