Firstly, that requires you to have a magnitude level of better institutional quality than you did under East Pakistan as well (more than the poor tax/fiscal imprint that was realised especially back then...and only slowly improves to this day) Thats quite a stretch of an argument to make.
Secondly , that institutional quality of yours (as seen in the corruption perception index) is much worse and still not improving (and worse than India and Pakistan)....so I doubt it suddenly would have been so great off the bat in the 50s - 70s. This
capacity did not start suddenly in 1971, we all inherited it from the British Raj and the real impetus to improving it in region only really started in post cold war time, well past 1971.
Thirdly, being part of Pakistan was your decision, you (or at least those in position to make and influence that decision) thus inherit how it turned out for you in the end. If you feel you were held back, well then you shouldn't have pushed for such a concept of Pakistan in the first place.
Plus
@DESERT FIGHTER and others have presented their side on how much the fiscal diversion actually was regarding the two wings of Pakistan. He can post that here again and discuss that. Essentially it came to showing the effective diversion rate accounting for the small imprint the fiscal structure of the govt had in the first place was not enough to discount 50s - 70s BD as null and void under some kind of total extractive monopoly (which say really existed only under the British at various periods).
and doing a lot better than Bangladesh....especially where it matters: institutional capacity. Because that's what determines the capacity of a country's govt to address its problems going forward. Also a major reason why BD will never diversify its economy properly...political corruption always prefers as few industries as possible.