Culture is effected by religion and in case of muslims, religion is the predominant identity of ones life. Naturally U don't accept muslims to have the same greeting, weeding, eating and social norms as their hindu counterparts do U? The only thing we have common with pagan WB is the language which is also different in dialects. Do u know the amount of arabian & persian words infused in bengali? Our psyche and perception is also different. WB consider them indians and identify with their fellow hindu brothers of India while we identify our selves as muslim Bangladeshis. It doesn't matter what our ancestors did. What matters is they reverted from their former paganistic beliefs and accepted Islam. The paganistic culture your are talking about is alien to us. Isn't that a no-brainer? Why beat around the bush? If U hate us for being muslims and who we are just say so straight forward like most of your fellow countrymen here without coming up with obscure & absurd logic of culture & ancestors. We have our culture and you have yours. Is that too hard to understand? We don't give a damn about what WB or Indians call culture , then why the hell do U folks burn yourselves up with lunatic level of obsession towards BDs?
And as for the turkic/arab ancestors. Well yeah its true. Arabs and turks did settle here when they bought the beautiful religion of Islam with them and freed this land from shackles of oppression and tyranny. SO yeah we do have arab/turk ancestory. why does that bother U may I ask?
Islam doesn't puts bar on any language. Allah (swt) gave different languages to different ethnicities and throughout the ages since the beginning of time send out prophets to all ethnicities & nations of the world to teach Islam and finally with his divine wisdom revealed the last revelation and guidance for mankind, the Quran in the beautiful language of arabic. Islam =/= Arab as it is for the whole of mankind. It is a religion that has been ordained by Allah (swt) for the whole of humanity and is there since the beginning of time starting with the first human being prophet Adam (pbuh).
So i don't get your logic of why we should abort the language, that Allah (swt) gifted us with. Rather we should produce more scholarly Islamic literature in bengali. This would help spread islam more quickly among bengalis living in the other side of the border. Not all non-muslim WBengalis understand english or Arabic U know. Muslims should have mastery over all languages so that we can spread the message of Islam to all ethnicities and help them learn arabic.