Further, I would add these little-discussed cases as well:
the hackers themselves will not store their stolen coins in QC vulnerable addresses, thus the quantum vulnerability of bitcoin will heal itself rather quickly.
Public labs and large QC entities (and any miners) that knowingly participate in this theft will be liable not only directly for the bitcoin stolen, but also from class action lawsuits from all bitcoin holders. Further such actions will go well past civil fines and will result in criminal penalties.
The second point offers another remediation that I haven't seen discussed: Legal Embargo.
Forget any changes to bitcoin protocol, simply a FINCEN related law / regulation is passed that (a) identifies all QC vulnerable addresses, and (b) sets a date (2030?), that says any transaction (mining, exchange, etc) involving those addresses past 2030 requires KYC and documented proof of ownership on those coins.
This isn't perfect. But it does offer a remediation - so whoever holds those coins (if still alive) will have a few years to move them KYC-free to safe addresses.
Further, I would add these little-discussed cases as well:
The second point offers another remediation that I haven't seen discussed: Legal Embargo.
Forget any changes to bitcoin protocol, simply a FINCEN related law / regulation is passed that (a) identifies all QC vulnerable addresses, and (b) sets a date (2030?), that says any transaction (mining, exchange, etc) involving those addresses past 2030 requires KYC and documented proof of ownership on those coins.
This isn't perfect. But it does offer a remediation - so whoever holds those coins (if still alive) will have a few years to move them KYC-free to safe addresses.