The scripting and automation in GC is fantastic. GenerativeComponents is a very powerful parametric modeling software.
No one uses it anymore. It was a niche product to begin with and over the last 5 years everyone who was using it is now working with Grasshopper (Rhinoceros) or Dynamo (Revit).
GenerativeComponents doesn't have many users anymore. There are newer, more popular software that can do what GC can.
Complex, repetitive modeling tasks and best handled with GenerativeComponents. The integration with Microstation Building is a plus but it was never realized to its full potential.