Personally I don't think that Bangladesh will face the same fate as that of Kenya or Canada. Corruption is there, but there is a lot of talent in Bangladesh. But competing against the big-4 requires consistency in addition to talent. At this point, I can't find anyone in the Bangladeshi squad who is consistent. Litton Das is the one who comes close to being consistent. Shakib al Hasan was consistent until a few years ago, but he seems to have lost his mojo. Among the bowlers, Mustafizur Rahman is comparatively better, but again not quite there.
Tamim, Mushfiqur, Shakib and Mahmudullah, these four senior and important players of Bangladesh will retire in the next few years. Bangladesh may have a lot of talented players, but not experienced players. When these four senior players retire, Bangladesh will not be able to find 11 experienced players for their squad. However, after the next World Cup, Bangladesh will face big problems.