I'm not sure about the level of technology Iran used for the cruise missiles or drones? From what I understand private drone tech is way ahead of most government tech which means its readily available for purchasing and Iran reverse engineers a lot of stuff. So their drone tech could be pretty good. Cruise missiles use various techs which include internal mapping and use of GPS. To me the accuracy of hits on the storage tanks indicates a high level of targeting tech and this accuracy would have been difficult with someone controlling them from 500 miles away with a controller. Some other tech is in play in this attack.