R Markdown/Notebooks, IMO, has evolved to be the key value proposition of RStudio over the years. From a productivity standpoint when both working with R and publishing pretty reports/PDFs it has been incredible. (that said, if VS Code gets more robust R Markdown support, I may consider switching from RStudio)
I wrote a blog post a few years ago comparing R Markdown/Notebooks to Jupyter Notebooks: https://minimaxir.com/2017/06/r-notebooks/