Nah, I don't think so. We're getting into philosophical / religious territory here, but from a technical standpoint I believe there is no difference between a brain and an accurate simulation of a brain, and an accurate simulation of a brain is "just" an engineering challenge at this point. We might now have the computing power or architecture yet, but there is no conceptual issue prohibiting us from building it.

But an LLM is not a simulation of a brain. It is an autocomplete on steroids. Very different architecture. It is not a brain, but it can sometimes produce the same outputs a brain would. But it is nowhere close to a human brain.