Just make sure you're printing on acid-free, high-quallity paper and that it's stored in an environment to prevent decay, yellowing, and other environmental issues. Because if just 1 tiny little block in the QR code becomes unreadable, or the ink/toner flakes off.
Flat out false. QR Codes have redundancy in them. Level H codes can recover from errors up to 30%.
That's like keeping all of your money in a safe deposit box, in cash, and only spending cash for purchases.
You need to be considering the case of people who have substantial amounts of wealth in Bitcoins. Say I have $100,000 worth of Bitcoins. What you are suggesting is that I make a $100,000 wager that I can keep my computer free of zero-day viruses, FOR LIFE. I am not willing to make that bet. It is, after all, a Windows machine.
Making backup wallets and storing them for years makes a lot of sense. Paper is far more durable than any electronic medium. What medium would you suggest that is going to last 100 years? Floppy?