While it doesn't support Linux, Backblaze is cloud storage and it's $70/yr for unlimited storage. To me, that's not a rip off for very secure off site back up. I backup my Mac locally to an external drive with Time Machine, many things (Photos, Mail, etc) are also in iCloud, and I use Backblaze.

If you only use local external drives, get more than one, and rotate them off site. All it takes is a fire or break-in and your computer and external backup drive could be gone. If you at least have a drive off site, there's a much higher chance that you'll be ok.

And then make sure to scrub it weekly to make sure the bits haven't rotted, and move it to another location every night to be sure it doesn't die in a house fire.

Cloud backups do help with disaster recovery. If your house burns or floods, you can recover your data anywhere without sifting ashes/fishing for your external drive.