There are two answers to this.

Answer 1: Some people think that LLMs are a path to the singularity, a self-improving intelligent program that will vastly exceed human intelligence and will be able to increase its knowledge exponentially, quickly answering all answerable scientific questions.

Answer 2: LLM companies need to keep the hype train rolling. I didn't watch the whole clip; I jumped around a bit, but I noticed that every time Musk interjected something, it was to exaggerate what was previously said. "Grok contains the whole internet"—"the whole of human knowledge, actually!"

I think that both answer 1 and answer 2 apply to Musk. He seems to believe that they're building a god-like entity, and he also needs to keep the money train rolling.