Doing paper backups is hard I could not store much data on paper when I last tried with QR codes. You need to to multiple QR codes since they are only 2KB each. There are some threads about it on HN, but I have never seen anyone do megabytes per paper
https://news.ycombinator.com/item?id=29792556 https://news.ycombinator.com/item?id=31149427 https://news.ycombinator.com/item?id=24669425 https://hn.algolia.com/?q=paper+backup Cuneiform tables do it in clay.