Agreed. R might not have the breadth of Python, and it's less conventional as a language (procedural, vector based).

It has some key strengths though:

1. RStudio IDE as you note. It's a really great, focused IDE for doing most of the things people do with R.

2. Shiny. Such a well conceived and constructed toolkit for building interactive apps

3. The package ecosystem: lots of really good quality, high performance packages

4. RStudio the company, who contribute a lot to the community - both open source (RStudio IDE, Shiny, tidyverse, ...) and commercial (RSConnect, Package Manager).

From a language design pov I like Julia over Python over R. But for number-heavy computing I prefer the R ecosystem overall.