Bangladesh prepared spinning tracks to suit their left armers and give them some advantage but in the process they have made Indian bowling appear great and masked the shortcomings of batsman. Ball is not bouncing high thus short ball tactic wont work easily against the batters and India have more than enough decent spinners to tie other teams down. On top of that if other teams decide to play more spinners to use the pitch it would again work in India's favour because unless you are Ajmal, spin doesnt really bother them. They can milk spinners whole day. So Indians should be thanking Bangladesh for providing them home advantage.
Its not that simple. I don't see other teams having as big a impact as Indian spinners. I'd put this down to Indian spinners actually bowling well. This article talks about it well
India v West Indies, World T20, Group 2, Mirpur : Amit Mishra, Bhuvneshwar Kumar head bowlers improvement | Cricket News | World T20 | ESPN Cricinfo
Our bowlers did brilliantly against sides that either play spin very well (e.g. Pakistan) or against a side that has plenty amount of IPL experience and have played our bowlers long enough in recent times in the IPL. WI are T20 champions, and have a big presence in IPL cricket. They know us like the back of their hands.
We are still fielding pretty sloppy, but if our bowlers can keep this up, we might be the team to beat this tournament.