Thanks for the reply! So just by turning off syncing it can serve as a backup solution?
Yes. It just won't be a good backup solution, because like I said, that's not what OneDrive was built to do.
If you're mainly looking to backup files that never change (video, audio, etc), then I think OneDrive is a viable backup solution, because you can then turn off syncing without having to worry about keeping local and cloud copies of the same files in sync (because they never change). That's more or less just a dump of static data that you'd use only for disaster recovery.
However, if you're looking to backup a large amount of documents that change often, then turning off OneDrive's syncing requires you to find out on your own which files have changed since your last backup and then manually sync only them. That is anything but a user friendly backup solution. Of course you could forget about all of that and just regularly dump all your files onto OneDrive, but due to bandwidth throttling, doing so regularly for large amounts of data can become a pain in the rear.
So again, in a nutshell, OneDrive just isn't a good solution for anything but the most trivial of backup problems. It's not that it can't work. It can, but only for very simple backup scenarios.
If you think you'd find yourself regularly backing up large amounts of changing files, and you want features that most people would associate with a real backup solution (like maintaining a history of file changes, doing differential backups, etc), then you're far better off going with a cloud solution that was built to be a backup solution (like AWS Backup and Restore), which OneDrive just isn't.