I have watched this vid multiple times being amazed again and again until I tried a didge that had similar shape to his. Have you ever played a modern long necked and big bowled didge? Did you notice the increased back pressure and how playing faster or making “tuts/trumpets” is easier? https://youtu.be/B5BWC7-r6w4?si=ajI_se4hk7oeplPd

https://www.youtube.com/watch?v=ex7yNsaIT8s