I also have plenty of complaints about the service (posted above), but there’s nothing weird about this policy as written.
What’s weird is when permanently connected drives get classified as disconnected (see my other post).
In fact, their marketing claims "Never lose a file again. Get unlimited cloud backup for your Mac or PC. Just $5/month."
Only on reading the help does it seem that if the client doesn't connect with the server within 6 months, then all your backups are gone. I'm not saying this is unreasonable, but it seems a bit counterintuitive given you are still paying for the service. I just still haven't found the bit about disconnected drives.
I really like Backblaze's articles on HDDs and they really seem to be customer focused, but I had to dig in the help to find this.
For something as critical as data backups, I prefer that those companies stay in business and charge something that's a bit more proportional to their underlying costs. That's honesty and fairness, in my view.