uhmm depends. In my opinion, what will make it "to experts" is the applications that Julia can provide for several problems. In that sense, I can tell you as a Mining engineer that most of the applications are out of my bounds. However, is my goal is to apply as much as I can to my projects. As an R native, Julia es more powerfull in terms of speed and performance, but I think that R with his tidyverse has much to offer for me yet.