Hi again,
I reread your answer this morning and I found your logic wonderful but I think there is a flaw there.
I am not against your opinion I do believe that GitHub or StackOverflow cannot measure the popularity of a software. But somehow I believe you compared apple to oranges.
excel, SAS, Power BI, Tableau etc... are commercial software
R , python , julia, scala etc... are open source programming language
commercial software don't keep their code on GitHub but open source libraries do
in commercial software you have only one use case and almost one way of achieving it.
open source programming provides a lot of libraries that do almost same things. that should be the reason for low stack overflow questions.
Hope you understand what I mean now. I was trying to compare R with open source programming paradigm where GitHub stars do matter for most of the people. And newcomers check these things too...
but thanks for throwing light on dual nature of R to me. that R can behave wave like in some situations and matter like in another.(pun intended 

)