Addressing the Diminishing Block Subsidy

In exploring innovative ways to extend Bitcoin's subsidy mechanism, a hypothetical proposal suggests utilizing a semi-friendly Cryptographically Relevant Quantum Computer (CRQC) to avoid the necessity of a hard fork. The plan involves implementing a soft fork that imposes new rules on how Pay-to-Public-Key (P2PK) Unspent Transaction Outputs (UTXOs) are handled. After a designated block height set five years in the future, these UTXOs would be restricted from spending unless specific conditions are met. Primarily, at least 90% of the funds must be directed to a designated "anyone-can-spend" address, while the remainder could be sent to another address as an incentive for the CRQC operator.

The "anyone-can-spend" address would further be regulated to only allow disbursements of a maximum of 0.1 BTC per block. This strategy aims to gradually reclaim the funds from roughly 1.6 million BTC held in P2PK UTXOs, thereby introducing an additional 0.1 BTC per block into the mining subsidy without increasing the total coin supply or requiring a disruptive hard fork. Assuming effective reclamation of these funds, this method could sustain the enhanced subsidy for more than ten million blocks, which translates to over 200 years at the current mining rate of 144 blocks per day.

This approach is specifically targeted at P2PK UTXOs because they are likely irrecoverable and would otherwise be vulnerable in a post-quantum scenario where traditional cryptographic protections fail. While some advocate for permanently freezing these assets, this proposal presents a dual-benefit solution that not only secures these funds but also extends the economic incentives for mining activities crucial for network security.