Theft and fraud aren't the same thing. Obviously, one can commit theft by the means of fraud. Fraud is a personal representation and trust relationship, and cannot be solved by a mathematical equation. A DEX might preclude the need for trust relationships in order to prevent the circumstances that make fraud possible, but it doesn't solve for fraud and, as FTX proved, crypto itself (using the commonly understood term, as opposed to the one you invented where the only things that are crypto are DEX) doesn't solve for fraud.
I've not at any point contested the differences between DEX and CEXs with you and you should really work on your reading comprehension so you can realize that.
??? Genuinely at a loss. You're conflating CEXs and DEXs to make a point about how "crypto does not prevent fraud". I said sure, if you want to include CEXs in "crypto" then "crypto" does not prevent fraud, but self-custody solutions like DEXs still do.
Because CEX's are undoubtedly part of crypto and nobody could say otherwise without being completely disingenuous. Which is exactly what our debate has been over.