That seems like a desirable goal, but that is beyond a simple renaming of the existing classes. The question at hand is what to rename these very OpenGL-specific widgets. They both rely on a vtkGenericOpenGLRenderWindow internally.
If you want to add that implementation-agnostic level above this now and advise people to use that, I have no objection. But as for a simple rename operation of these classes, I am arguing OpenGL should stay in the name.