How are those decentralized exchanges gonna cash you out without knowing your name and IBAN? People who do these transactions will be targeted this time. When people move to dex, the volume will skyrocket there. I don’t think you can get in and out so easily when that happens.
You will still trade normally by handing over your IBAN. If things become ever stricter than that, and they start freezing your bank account because of this, there is still cash.
From my bank's perspective, receiving money from different unknown IBAN accounts is much more questionable than receiving money from an established centralized exchange. The same with sending money.