PQC - What is our Goal, Even?

The discussion within the Bitcoin Development Mailing List highlights notable concerns and considerations regarding the implementation of new cryptographic methods in wallet address management, specifically addressing the transition from P2TRv2 to P2MR. The primary challenge identified is the longstanding issue of address reuse by wallets. Despite efforts spanning over 15 years aimed at encouraging the discontinuation of address reuse, there has been minimal progress. In fact, many popular wallets have moved in the opposite direction, continuing or even increasing the frequency of address reuse. This prevailing trend undermines any potential benefits that the proposed P2MR method might offer over the existing P2TRv2, as the advantages of P2MR are nullified if old habits persist within the ecosystem.

Moreover, the conversation touches on the technical complexities associated with adopting P2MR. It is noted that integrating such a system goes beyond simple updates or installations (e.g., not just an "npm install whatever"). It necessitates a comprehensive rewrite of several underlying mechanisms, including key derivation and backup schemes. Additionally, this shift would require altering user experience (UX) decisions that were originally made based on extensive user feedback, thus adding another layer of complexity to the adoption process.

The dialogue also reflects a broader perspective on maintaining the original goals set during the development of taproot, emphasizing that the change is not merely about reducing transaction fees but also about achieving long-term security, flexibility, and optimization objectives. However, it is acknowledged that without significant changes in the operational processes of the ecosystem, P2MR will not be effective. These insights underscore the intricate balance between technological advancement and practical implementation in the field of cryptocurrency development.