Having seen how he tracked a couple of my own flights I can see some value.
In both cases he was given a departure point (outside of Australia, outside of both radar and ADSB), an initial heading, but not an arrival port. In both cases he was able to accurately to show not just where we landed (two very different ports) but also our arrival time with an accuracy of a couple of minutes. His enroute ETAs were all within a couple of minutes of ours also.
It’s better than throwing darts in a map and seems to be much better than a ouija board.