Just to interject, Bangladesh government as far as bitcoin is concern is on the grey area, so meaning Bangladeshi can trade, own as it is not a crime per se.
You may need to read this news, if Bangladesh Bank know your money came from cryptocurrency you will get jailed. It's tend too illegal rather grey area.
Bangladesh Bank has once again said today that it does not allow holding or trading of any kind of virtual coin or cryptocurrency in the country.
But in order to get more elaborative insight or get better results its surely need to conduct a survey on a well-established enough samples.
It's bad idea since you will get reported from your respondents since you doing a illegal survey, it will only make the surveyor in trouble. You will need to face legal law's on Bangladesh authorities.
If Bangladesh doesn't want to legalize Bitcoin it's okay, but at least make Bitcoin not illegal since it make Bangladesh citizens doesn't have a full freedom. I agree with @DdmrDdmr and @teosanru, the poll isn't accurate due to lack of participants with unpopular social media. Based on my perspective about Bangladesh citizens, seems they didn't want to legalize or doesn't care about Bitcoin. Most of third countries is poor and scared of Bitcoin volatility.