I am curious where had you found the rules that users will be ban posting threads out of the local board?
That's a direct quote from the
stickied thread in the other languages board.
There are dozens of threads stickied in the other languages sub, and the thread stickied is at the bottom (a non-conventional location). When I first read this thread, I had trouble finding the thread with that rule.
Thank you PrimeNumber7 for pointing out some true facts. Bengali should be given a dedicated board.
but I suspect it is at least influenced by their inability to create threads to discuss specific topics in their local language.
This is the most important reason why people don't discuss in the local thread. It's very hard to discuss things in a single thread. You don't know what has been discussed or shared, you can't find a piece of specific information because there are hundreds of pages to check out.
These are all compelling reasons why a new thread with important/useful information being in a central location should be allowed.
I don't think you will be given permission to open a new thread though. As I mentioned previously, I think it would be better to create a new dedicated sub for your location. The cost of doing so would be trivial, and there would be tangible benefits.
You might be able to make the same argument for opening a thread for many other languages in the 'other languages' sub, and allowing for two (or more) threads per language would only clutter that sub in a confusing way. I think it is unlikely you will be banned for opening a single duplicate thread, however i think there is a good chance it would get removed.