His comments might have some weight if he actually provided evidence of his assertions. For instance he says "it doesn't know what the words _mean_." How do we indicate/prove that we know what a word means? We can give a definition. We can offer an example of how to use it in a sentence. We can explain and/or demonstrate how its meaning can vary depending upon context. Etc... ChatGPT can do all those things.

So, is there something more fundamental going on in our own brains? If so, what is it?

As far as false vs. true, humans also make many mistakes, confuse references, draw false conclusions drawn from unrelated evidence, and on and on. We also often get things right. ChatGPT is similar.

He just makes conclusory statements so it is just an opinion. I'm not saying any true intelligence has been demonstrated yet, but the progress that has been made in just the last year or two has been enormous. Does anyone doubt the progress won't continue? Something very important is happening and I personally think it is more than just "playing games with words." Just my opinion...