Not the poster, but: use ZFS or LVM + XFS on your machine, do a snapshot, use restic or kopia to back it up to cheap object storage in the cloud, such as R2. If it's too technical, run syncthing and mirror it to a USB-connected external disk, preferably a couple of meters away from your machine.
A poor haphazard backup is better than no backup.
> A poor haphazard backup is better than no backup.
but is it better than cloud provider?
Cloud provider can lock you out without recourse and you'll lose your data.
Local backups can fail, be destroyed (for example a failed PSU kills both your PC and any attached devices), or be deleted by malware
How complex do you need to have your local backup to achieve cloud providers' reliability?
The best backup is a proper 3-2-1, with regular testing of integrity, and regular restoration from a backup as an exercise. But most people cannot be bothered to care quite so much.
So, keeping a half-assed backup copy on a spouse's machine in a different room is still better than not keeping any copy at all. It will not protect from every disaster, but it will protect against some.
My own backups progressed from manual rsync to syncthing to syncthing for every machine in the house + restic backups (which saved my bacon more than once).