The game-theory problems of PQ sunsetting modes

The discussion raises an important point regarding the potential vulnerabilities of sidechains and altcoins such as Ethereum, particularly in the context of quantum attacks. It is suggested that these blockchain technologies might be more inclined to implement a hard fork as a response to recover from an attack. This approach contrasts with other systems that may not offer such flexibility to reverse transactions following an attack, which could render efforts by quantum attackers futile if they seek irreversible damage.

A specific example provided includes a detailed exploration on how Ethereum could potentially handle a quantum crisis by hard forking to save users' funds, which can be found in a research post available here. The ability to revert via hard forks might discourage quantum attackers since their primary goal is often to achieve irreversible impacts, making their attacks definitive without possibilities for mitigation through such forks.

This concern underscores the broader strategic considerations that must be taken into account when securing blockchain technologies against emerging threats, highlighting the balance between finality and adaptability in blockchain's design and response strategy.