I have 3:2:1 for my crucial data ( pictures of family and travels and digital documents like tax returns). Basically one main copy another copy on an old nas with shucked drives not connected to the internet and one cloud copy. It is worth it because I would hate hate to lose that data.
I have 2:1 for my media. Just a local copy . If the apartment goes up in flames or a freak lightning burns it down I will have to re-download it again or I will live without it and ghats fine. For a long time the media had no backup but just raid and snapshots to protect against hard-drive failures and dumb user errors.
It's all about your means and risk appetite.
A 10tb+ shucked ( buy an usb enclosure and break it open) drive is a good low coat approach with some risk
So they are often great value for money with some caveats