The withdrawal systems and the exchange accounts are all still centralized on the Hive Engine. That's the only part where it is centralized. Other areas are decentralized.
That's also because the Engine team wants to have control over what is happening on the Hive Engine. We have few other challenges and scalability issues that need to be sorted before we think about having open smart contracts and more decentralization. But yeah the future should be like that. Let's see.