A large increase in traffic to and from mixers, and a large decrease in traffic to and from centralized exchanges. I don't find this surprising at all. As time goes on, centralized exchanges are more and more turning themselves in to self appointed judge, jury, and executioners for people who use them. They track the movement of your coins long after you withdraw them from the exchange, and they look back at the history of your coins long before you deposit them at the exchange. If they don't like what they see, your account is locked and there is nothing you can do about it. If you perform some arbitrary "suspicious activity", your account is locked and there is nothing you can do about it. If you deposit too much too quickly or withdraw too much too quickly, your account is locked. I'm sure that plenty of coins that have touched a darknet entity have been locked, frozen, or seized as soon as they touched a centralized exchange, but this isn't just the case for darknet entities. There are centralized exchanges policing perfectly legal bitcoin usage, such as to and from casinos and gambling sites.

We will continue to see the popularity of mixers and other privacy enhancing techniques such as CoinJoin and PayJoin increase as time goes on.