I think that Binance DEX is a hybrid exchange. I think that its not very bad that Binance Dex works on a centralized blockchain. Its important that Binance continue to be a good conscientious exchange.
DEX is not an hybrid exchange site but the developer still has the full control over the exchange site dude. But this party can be trusted and it's not a big problem as long as the team can still become the trusted guys.
It is not only about the trust. They can get hacked or lose money or tokens some other way. When that happen to centralized exchange everyone's coins are in danger. In decentralized exchange they are nto since you control your coins until you dot exchange and then you control other coins. They dont hold your founds. So no risk. No cold wallets no nothing.