Is it normal Python trace doesn't record some operation?

Python tracing and state files rely on inserting code that tells what code should be generated. As ParaView is a large application, there are unfortunately some gaps in tracing completeness. Over the years, these gaps have decreased as we make sure to add Python tracing code as new code is added to ParaView. It isn’t perfect, as you have discovered, so reports like these are helpful for identifying and fixing those gaps.

As it happens, we have an issue report for this here: It will be addressed like any other bug in ParaView. For more info about that process, please see How are features and bug fixes incorporated into ParaView?