Google does not really own the complete AI stack, NVDA is extracting a lot of the value there.
Google has two other impediments to doing what ChatGPT does.
Googles entire business model is built around search. They have augmented search with AI, but that is not the same as completely disrupting an incredibly profitable business model with an unprofitable and unproven business model.
Also... Americans are in the habit of going to ChatGPT now for AI. When you think of AI, you now think of ChatGPT first.
The real risk is we are at the tail end of a long economic boom cycle, OpenAI is incredibly dependent on additional funding rounds, and if we recess access to that funding gets cut off.