Is this on-topic or off-topic? in case off-topic how can I reframe the question of why R is few used in AI? or all is off-topic?
Is on-topic ask about the lack of R tagged questions in ai.stackexchange?
I am not sure I understand this question. If you're asking whether it would be on-topic/off-topic to ask a question on our main site about why we don't have many questions tagged with the R programming language, then the answer is "yes, it would be off-topic". That question is better suited for meta (i.e. here).
how can I reframe the question of why R is few used in AI? or all is off-topic?
I think that asking something like
Why isn't R widely used in AI?
will lead to opinions. Some people will say that it's used in many cases, and other people will say "Because Python is better", which I am not saying, of course, that is true or false.
I think a question like
What characteristic of the R language would make it a "good" language for AI?
would be more suitable for our site. But we already have a similar question here, and we closed it as off-topic. For some reason, I had also voted to close this post. However, we have other similar questions on programming languages that were not closed. For example, this one.
To be honest, I think we really need to clarify which type of questions on programming language would then be on-topic here on our on-topic page. This is a good time to do it.
The first post was probably closed because the OP was looking for a piece of advice on which language is best for data science. That will lead to opinions. One could say "R is good because it has this data structure", but one could also say "Python has also that data structure", and so on. So, this type of question, where one compares one language to the other, will lead to debates/opinions, not just in AI, but, in general, in computer science or software development (this has been the case, historically), so I would say that this type of question should be closed for these reasons, although they can be useful for many people. For example, I think that the answers to that first question can be useful. In particular, in my answer, I try to list the strengths and weaknesses of both languages. Nevertheless, this type of question, as I said, can always lead to opinions and debates, so we should avoid it.
I think that questions on programming languages that are related to the history of AI would and should be on-topic here, as questions related to the history of AI are on-topic here.
Why was LISP widely used in the early ages of AI? Which characteristics of the LISP language make it suitable for what people were doing in AI in the beginning?