Earlier quoted context omitted.
I think that's unlikely to be a thing they're working on. You can get that from storing your files in iCloud already, and these days is there any good reason to back up the rest of your system? If I had to rebuild a system due to hardware failure the absolute last thing I'd want to do would be restore all the accumulated system cruft!
iOS devices do full backups to iCloud†, restorable onto a new device just like macOS full Time Machine backups are. So why not macOS backups in iCloud? If anything, you'd expect it to be the other way around—in iOS devices, you/apps can't litter your homedir with random garbage, while in macOS you can. So it's more useful to back up macOS. † You can also make an iOS backup onto a local macOS computer running iTunes,…
One example: apps that you built onto your device as a developer. Get a new phone and restore from backup? That app is gone now.
I do understand the reasons why. But understanding does not make it a full backup.