I think both India and Pakistan team is going through a bad phase at the moment.
I agree. India and Pakistan need to improve in several key areas in order to climb back to the top across all formats, but it's going to be very difficult thanks to Australia, England and New Zealand consistently performing well these days.
It is true that the bangladeshi bowlers have performed very poorly but event then I think it would be partiality to blame them only because the bangladeshi batsmen were all out for less than 200 runs. To see, they have performed poorly on both sides batting and bowling.
Pressure screwed them in that game. Chasing 400+ target would seem daunting for any team. They failed in all departments in that match, but still won the series.