Don't be surprised and the government will always use that excuse and it's also commonly used by countries that block online gambling sites.
My guess is actually not money laundering that is their focus but their inability to collect taxes from online gambling activities the reason behind this blocking.
Which usually happens when the government does not benefit from the activities carried out by its people, the steps taken are prohibiting, blocking and so on.
I do agree with you. It's caused by mostly of gambling sites are not based in their countries and that makes them can't collect it. There was also another reason other than it but it only knows by the government. As long as people can still access it easily and there no need to feel doubt about that. The fact that if these days people may able to pass the block that already made by the government. The government was only blocking the site. It can be accessed use alternative link or easily. Bangla is not the first country wo ban hundreds of casinos. There are another countries that have been doing the same thing like bangla in the past.