Only if Haskell stops being maintained, which I very much doubt would happen. Therefore no one is forced into the change.
Now, perhaps the problem in your eyes is the old version isn't being maintained. But I see the opposite: maintaining two versions indefinitely is the problem. The Haskell community is not infinitely big, nor growing fast enough, that if e.g. 1/2 went to Idris and 1/2 stayed, it wouldn't be catastrophic.
Making the changes we need to make, and then making it as easy as possible for everyone to migrate, I think is the best way.