We’re talking about an order of magnitude difference in number of packages (82096 on PyPI vs. 8551 on CRAN) and their maturity, and such a naïve metric probably undersells the difference in variety of use cases.

If you picked 100 random production python projects out of a hat, no more than a small handful of them would be remotely appropriate to build using R.

And that's entirely fine. R is great at being a quick and dirty statistical analysis language for people doing data exploration.