I have access to Gemini pro, indeed, it is smarter. But not everything we need to use AI for needs the smartest one around.
I am using Gemini pro to help plan for advanced game mechanics for the Buddhist video game, but using notebook LM to extract from the texts what dhamma states to use in the game mechanic.
Even Gemini itself recommended such split of tasks.
In terms of factual accuracy, NotebookLM should be better.
In terms of deep questions with creativity, and deep thinking, likely Gemini pro is better.