Getting people to switch to R (or Julia) from excel is to balance two competing goals.

First, you need to establish that scripting is far superior to point-and-click interfaces via reproducibility and legibility. This is the fight worth having, as it gets to the core of what it means to do science and share results.

Second, you need to convince them that they don't have to sacrifice the tractability and ease of use of excel. Jupyter notebooks, for all their faults, really sell this idea well. But the first goal should dominate the second. Nteract and shiny are great, but I they are big tools that are difficult to teach beginners to code up. We shouldn't say "use R because you can still use point-and-click interfaces", we should argue against point-and-click interfaces all together in this context.

I also agree with the poster below that running a script again with a new parameter changed is super super easy, and you dont need a GUI to explore data like that.