If you ban CEX worldwide, crypto it will still usable peer 2 peer. But of course you'll kill 100% of the crypto using public ledger.
And privacy coin will trive, Monero will become the new BTC, Dero the new Ethereum and that's it the Defi and NFT will still be there but they'll be running on Dero instead of Ethereum. So banning public crypto is a lose for government because they'll lose the traceability but crypto will be still here protecting people from government tyranny.