In fact, since we do know the basic fundamentals of how brains work, it would seem that’s exactly what’s happening.

I encourage you to try to find and cite any reputable neuroscientist that believes we can even quantify what thought is, much less believes both A) we ‘know the basic fundamentals of how brains work’ and B) it’s just like an LLM.

Your argument isn’t a line of reasoning invented by neuroscientists, it’s one invented by people who need to sell more AI processors. I know which group I think has a better handle on the brain.