Proper scalability is definitely required, not only an overall scale but also need X, Y, Z scale for both 2D and 3D elements.
One excuse of not provide scalability is that Revit is for modelling real world objects, such as a room. You can not scale a room with columns etc all scaled up. But this is not always the case. There are scale requirement for 3D objects for sure, especially when designing these objects, for example, a statue, you may want to scale it, and maybe even scale it differently in X,Y,Z directions.
In Revit the only element category can be scaled is "Planting". This is definitely not enough. At least Generic Model should have scalability (X,Y,Z).
For 2D stuff like Detailed Items, Generic Annotations, etc, scalability should be a must too.
As a design tool, Revit should help people being creative, not stop them doing so.