This was a GOOD thread, although I couldn't participate freely.
Also, to clarify, there is ONE set of members who believe that there is a Sylheti language. Many others believe that it is one more dialect; in this, besides following
@Axomiya_lora, just read the posts by
@Homo Sapiens; between them, they provide a very good perspective from two points of view, and it rather nicely sums things up. That is NOT to say that what the OP claims is untrue; just that there are various opinions on the matter.
To a speaker of Assamese, or the central Bangladeshi dialect, or, I suspect, equally to a person from Tangail, it is not excessively difficult to understand the general drift of things; it might not be possible to reproduce it, but it is possible to understand it.
People from other parts of India have to get it on board that the east is different; we are not people who speak Hindi with a bad accent.
Just edited this: we are not people who speak Hindi with a bad accent; we don't care to speak Hindi, but when we do, our accent is usually better than the way a Maharashtrian or a Gujarati murders the Hindi language.