Are users encouraged to ask simple math questions in this forum as well? Most of the questions here seem advanced for a math learner.
Yes, this is a Q&A site for mathematics at all levels. However, all questions should be asked well, regardless of how "elementary" or "advanced" the content of the question may be.
In particular, a math question at any level which follows the excellent guide How to ask a good question? should be warmly welcomed here.
You are not wrong that most of the posts on this site are at an Undergraduate level; however, all are encouraged to ask questions here!
Though I have no facts to back me up here, I would say that the prevalence of undergraduate material largely comes from the way schools and universities are set up:
- Prior to university, students in mathematics classes often have a teacher to whom they can go for help; when this is not an option students tend to do less and to succeed less often. Responsibility for the students' success is often seen as being placed solely in the hands of the teachers, and not in the hands of the students themselves.
- Once at university, students are given far more autonomy, and much more is expected of them. Due to the greater number of students, professors are less likely to gain a personal relationship to each student; accordingly, when students fail to understand material and seek guidance, the professor is not (or at least is not seen as) the best source of help and guidance. Instead, students consult the Internet, and are directed to MSE (most of the traffic to this site is from search engine redirects, as is true of the Stack Exchange network as a whole).
The most common plagues for lower-level questions seems to be lack of context, lack of work, and lack of thought. However, these same challenges face students at all levels, and everyone can ask a question here as long as he/she adheres to the appropriate guidelines.
Well, in theory, the site is supposed to be for "mathematics at all levels".
But in practice it seems that questions about elementary arithmetic are getting closed as "too narrow/specific, and not likely to be helpful to future readers". Students of elementary arithmetic will probably not be able to formulate general abstract versions of their questions; they only know about the specific problems that are causing them trouble. So, looks like those folks are out of luck.
Personally, I don't like this point of view. It's basically saying "your question isn't worthwhile because you're the only person interested in the answer". That's pretty unfriendly, in my view. And, AFAICS, there's nothing in the question guidelines that says that the question should be of interest to a broad audience. Helping the OP alone is still a worthwhile endeavor, IMO.
From what I have seen so far, if a question is asked in a polite way and shows context and effort, you will get a fair response. People are genuinely trying to help. But a simple mistake (typo) could alter the meaning of the question considerably and for mathematicians it is a frustrating experience to figure out what you intended with what you wrote. If you want to use this site, read, ask a question, contribute, build up your reputation and enjoy.