In instance, a lot of new research on statistics is done in R, mainly because is the standard in the industry/academy. If you want to use some new algorith you just readed about on a Journal, it will be implemented almost surely in R.

Julia have been trending for a couple years, and now a lot of researchers publish both R and Julia packages, it seems that in the future most research will be done in Julia.

TL;DR: If you just need basic statistics, interval estimation and alike, then you can use whatever you want, but if you want to use state-of-the-art algorithms. R/Julia are the tools.