I've grown to appreciate R, especially its plotting ability (ggplot).
But a few weeks back he asked me how to do some kind of data sorting / manipulation in R. My answer was that it was a 10 line Python script and I gave him the code. Alas, he couldn't figure out how to save the script and run it from a command-line.
You can't underestimate at how important Rstudio is to the popularity of R for non-programmers.
Most programming IDEs show the code but hide the data.
Excel shows the data but hides the code.
RStudio is awesome because it shows both the code and the data.