In StackOverflow, when a user asks a similar question to one that was already asked, most of the time the question gets closed with a link to the "original" question without being told why the question is similar or how the answers to the "original" question can help the author.

That might be OKish for us experienced developers. But for a total beginner, I find this approach to be unsuitable. Most programming beginners don't even know how to phrase their question because they are not sure what they are struggling with themselves. Most of their posts will be like "There is something wrong with my code but I can't figure out what it is". That would not have a place on StackOverflow ; the post would get downvoted to infinity and the beginner - who is just looking to learn - will most probably say "Ok, StackOverflow no more" and move to other media for help.

One time I asked a question about Perl semantics ; I could not figure out the behavior of a program I wrote. My answer got closed and redirected to another question that did feature a similar program to mine, with a similar behavior. But the answer to that question was not it. It was not explaining the wrong behavior on my program ; although it was similar. At the end of the day I did manage to figure out what was happening ; it turns out it was an effect different from the post that was linked. I tried to make an Edit and asked for reopening my question in order to provide the real answer to that question but I think that did not get accepted.

Actually, now I cannot even find the question in my profile anymore. It probably got removed altogether.

I agree that the multitude of programming help communities is a problem and my proposition would exacerbate that. But StackOverflow is clearly not the answer for me.