Phrased another way, “bug immortality guarantees.” What is the use case for completely immutable software? Even Ethereum smart contracts do not actually guarantee the compiled byte code matches the supposed source of the contract, so while it might be immutable, it is not free. I think the bigger concern is not that the code will update - updates are good, especially ones for bug fixes like the log4j vulnerability recently - but that the code they say is running, is not actually running.
And let’s assume that we need to update our code. You need to pay to deploy an entirely new contract and then have some sort of “pointer”/gateway that redirects all your users to the new patched contract, and then we’re right back where we started where this gateway can be forced by law to not direct people to your contract much like Google can be DMCA’d to not show copyright violations.