The best solution is one that would also require the exchange creators to make 0 profits. You create a wallet that has multiple wallets integrated into the same wallet, and allow for transaction fees to be the exchange fees, and thats all it would take to make a true dex, one that users hold their private keys - but, it would give no profits to the creators and thus has been no incentive to create it.
Also, DEX maintainers are still responsible and liable, as can be seen from ETH's DEX owner who was arrested recently
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