The solution to this problem is: - ban centralized exchanges - enforce stable coins to have their own coin-to-fiat exchange - allow only decentralized exchanges that can operate only if they implement some interoperability standards like dex-to-dex bridges - allow coins on decentralized exchanges only if they implement interoperability standards like blockchain-to-blockchain bridges

Now everybody can safely swap and transfer coins on whatever dex. If they want to cash out, swap again for usdt, then go to usdt official exchange and get your $.