I made this point in another comment: this is not a failing of the blockchain.
To compare, imagine an E2EE chat app built on Matrix protocol is blacklisted in your country. Anybody attempting to use it is treated as criminal, and the app will not be accepted into your country's App Stores. Does this mean the Matrix protocol has failed to deliver on its goals of end-to-end encryption?
In practical terms, it is very possible that a government can "shut down" the usefulness of a blockchain for many people. They could go as far as to criminalize any person who is found to be hosting their own blockchain nodes, or sending or receiving message packets to an RPC without first going through a centralized and permissioned service. If this were to happen, people would not willingly be using a blockchain out of fear of prosecution. Some countries like China and Russia seem to be moving in that direction, and some might argue the US too with their strong-arm censorship of Tornado Cash and all things related to it.
The government can blacklist all they want, they can't prevent you from transferring your assets to someone else. They can't freeze ETH like they can freeze your bank accounts or traditional capital assets.
Until the government decides to blacklist your account.
Ethereum is only decentralised until it isn't.