Once a subprotocol has been registered in the SubprotocolRegistry there is no way to update any of the values. The SubprotocolData.owner is the fee recipient leveraged as the fee recipient in CidNFT.add - which means it may continue to collect fees overtime.
Since subprotocols are created by more than just the inner dev team, it may be more likely that the wallet becomes compromised or the subprotocol team desires switching to a multisig address in the future.
You could allow transferring the owner to another address, potentially with a 2-step process. This would not negatively impact use of the subprotocol, nor change the associated gas costs.
Similarly, consider allowing other fields to be updated. For example, maybe the subprotocol owner can lower the fee at any point but not increase it.
