Changing Bitcoin’s supply cap from 21 million to a higher number would require a hard fork in the Bitcoin protocol. However, this is highly unlikely for several reasons:

1. Consensus mechanism: Bitcoin’s decentralized nature means that any major change requires widespread consensus among the network’s participants (miners, nodes, developers, and users). A proposal to increase the cap would need to be agreed upon by a large majority, but this would likely face strong resistance.

2. Core principle: The 21 million Bitcoin cap is a fundamental part of Bitcoin’s design, aimed at ensuring scarcity. Many Bitcoin supporters see this as essential for preserving its value proposition as “digital gold.” Altering this could undermine trust in the system and lead to a significant loss of confidence.

3. Hard fork: A change to the Bitcoin cap would require a hard fork, meaning the creation of a new version of Bitcoin incompatible with the current one. If the new version were adopted by only a minority of participants, it could lead to the creation of a separate cryptocurrency, as happened with Bitcoin Cash in 2017.

4. Incentive structure: Miners are incentivized by block rewards and transaction fees. As Bitcoin’s block reward halves every four years, eventually transaction fees will become the main source of revenue for miners. Increasing the cap might delay the shift to a fee-based system but could also negatively affect Bitcoin’s long-term sustainability.

In short, while technically possible, changing Bitcoin’s supply cap would be a complex and controversial process that is unlikely to succeed due to philosophical and economic factors.