I'm pretty sure that whatever solution the r/datahoarder people go for is exactly the one I DON'T want to choose. Those are the exact people who make attractive pricing unsustainable.
Maybe you don't like the way they abuse their accounts, but it doesn't mean their tools are bad.
It does mean the tools are more likely to be driven out of business, though.
Duplicati is backup software only; you bring-your-own-(local or cloud)-storage.