If Pakistan, India & Bangladesh were still 1 country there would be 630 million Muslims. Would South Asian Muslims be more powerful in this scenario?

Currently there are around 240 million Muslims in Pakistan; around 230 million Muslims in India (assuming past growth rates, since there have been no official census results published since 2011); and around 160 million Muslims in Bangladesh. For a total of 630 million South Asian Muslims in 2025.

Considering the problems faced by Muslims in Pakistan (terrorism, Shia-Sunni conflict, politics); in India (persuction during BJP rule and otherwise); and in Bangladesh (entirely cyclone and flood prone country) today... would such a large Muslim population spread across a united South Asia have been preferable to the current situation?

What are the pros and cons?