My question is: can materialized views be updated incrementally. For example:

In my case, we store the data in Iron layer and it gets flattened in bronze and silver layer as separate tables. The required transformations happen from silver to gold layer.

All the Iron, bronze and silver layers are streaming tables as SCD type 2 and gets incrementally loaded. 

The Gold layer are materialized views. Every time the pipeline runs, the materialized views are fully refreshed. But we wanted to have those incrementally loaded.
Example: