I personally am fine with this.
Printing recovery codes would require me to either be price gouged by the printer ink cartel or use someone else’s printer, and using someone else’s printer is begging to get my account stolen.
I have no idea how to hammer things into metal plates, but I’m guessing that’s even more expensive than printer ink.
I can do that with alphanumeric codes, yeah, but can I get alphanumeric codes from GitHub, or is it going to be a QR code? I can’t write down a QR code…
QR codes are just an encoding. Just use any half-competent QR code app, and it will give you it’s content, which you can then write down. For the reverse you can use any QR code generator.