schweizer I'm glad that what you describe is working for you, but for me it's just not the case.
I doubt that a full backup is what most users need. I never had the case that my phone would be corrupted in a way which would make a backup restore on the same device useful.
The reason for a "full" backup is when the whole setup needs to be recreated after (for whatever the reason) a full wipe. I don't know about you, but for me such happens almost monthly. With a "full" backup, it takes me a couple of hours to bring it back to it's fully configured state vs. 2-3 days of going through every system setting and every app's setting anew, and over, and over... it gets boring very quickly. So, at least for me, it's root>backup>unroot and keep on going until wipe>reinstall_OS>root>restore>unroot>adjust and keep on going as if nothing happened.
When the phone is broken or stolen you get a newer device so a complete backup is not useful since it might not be compatible.
A full backup for me it's all the apps and and their data, and that it's compatible across Android, as long as one sticks with the same architecture, which is true for Pixels.
Also full backups are expensive since they include lots of data.
I'm starting to have questions about your understanding of what gets backed up in "full backup". Take a look at SwiftBackup, for example. One gets to choose which parts of app's space gets backed up, and then restored.
A much better option is to sync specific data such as images contacts calendar chats and the password database. Such a backup does not contain unnecessary data and it is easy to restore on a newer device. I do this with Foldersync as well. On the server side the dara is useful as well since you can use it on other devices. The server might need an offline backup though.
This is all well and good, and I wish it was the case that every app had a data export/import facility, but that's far from being the case, and most of my apps actually don't have that, so in my case it's the app's data that it's "priceless" to me.
BTW, Seedvault, which is the currently sanctioned backup app, besides being unreliable, will not backup older apps at all.
We are not in a good place yet with a proper backup system, and I, myself, can't wait for @GrapheneOS to finally roll it's own, long promised, backup solution already.