I'm not sure it was ever the goal that everyone would _speak_ Rumantsch Grischun, as it is called, but the hope was that at least it would be used in writing (e.g. in school books) [1]. The resistance there is arguably more surprising.
[1] This is not too different from the situation with High German being used in education even though everyone speaks in dialects.
Is the goal perhaps more that this merged dialect could be intelligible to the speakers of all the dialects, such that it could be used to issue copies of laws that they could read, etc.?
[1] This is not too different from the situation with High German being used in education even though everyone speaks in dialects.