PQC - What is our Goal, Even?

The discussion within the Bitcoin Development Mailing List emphasizes a critical viewpoint on the security assumptions in quantum computing as they relate to cryptographic signatures. Specifically, the argument presented underlines that if a quantum entity possesses the private key, traditional proofs to safeguard against signature forgery become ineffective. This point challenges the commonly held assumption that quantum efforts are primarily focused on forging signatures using public keys alone. The clarification provided in this discourse sheds light on the necessity to rethink security frameworks in cryptographic systems, especially considering the advancements in quantum computing capabilities. This highlights an urgent need for developing robust security measures that are resilient against potential quantum computational attacks that bypass conventional cryptographic defenses by accessing private keys directly.