I only know that rather than Muslims our Hindus cook delicious vegetable foods with the addition of many different ingredients. Even Daal in a Hindu family kitchen has some special flavor and taste. Muslims usually eat vegetable as a side dish, but sometimes also as the main dish. However, all Muslim families regularly eat Daal. I am not aware if veg has become a trend in Bangladesh. But, i believe it will be limited to a fad instead of a trend.
By the way, I tell you one story about my experience with the Hindu owner of a tasty Sweet shop in my local Faridpur Town. He asked me why a tiger is so speedy, cruel and ferocious? It is because it and others such as lion are meat-eaters. On the contrary, goats, cows and others are docile and soft because they feed on grass/vegetable.
I think he had a point. Now, you will see the Muslims are traditionally not soft in nature comparing to their Hindu neighbors. The shop owner was implying this point by saying it is so because Muslims are traditionally meat-eaters and Hindus are not.
Note also that BD Hindus are nowadays emulating Muslim traditions and are eating more and more meats. Family kitchens would certainly not cook beef, but young men would eat this forbidden item in the eateries.