In the HAM Radio world we use them. But we also use our own infrastructure. I have mine set to let me know when something happens that needs my attention asap. Only works around my stuff or other HAMs that have stuff tied into our system. So not useful outside narrow circumstances.
Restic, it has native S3 compatibility and when you combine with something like B2 it makes amazing offsite storage so you can enjoy the tried and true 3-2-1 backup strategy.
Also fedora magazine did a few posts on setting it up with systemd that makes it SUPER EASY to get going if you need a guide.
I have an ansible role that configures it on everyone’s laptops so that they have local, NAS, and remote, B2, backup locations.
Works like a charm for the past 8+ years.