There is a tool called qrazy box
https://merri.cx/qrazybox/
It allows you to essentially remake a damaged or partially hidden QR code pixel by pixel, but has some limitations.
Basically, we put data into QR codes the same as hard drives. Why then are there so few data recovery tools for QR codes?
If a cat shows up on your doorstep and now you got to figure out who owns the cat because you become concerned about it over time, what do you do if you can't scan the QR code on its collar?
The point is that in general, QR code content is less important than hard drive content. And that (the low demand) is the simple explanation to why there aren't as many tools for recovery.