That's the point, though. As you say there is obviously enough information to learn grammar given our starting point, but Chomsky's point is that there's not e

That's the point, though. As you say there is obviously enough information to learn grammar given our starting point, but Chomsky's point is that there's not enough information to distinguish between all possible languages, so (paraphrasing from a decades-old recollection and probably very much putting my spin on it) learning a (first?) language as a human is probably a matter of figuring out how to apply existing "machinery" that imposes some of its own structure rather than operating entirely from the information provided to the senses. I'm not saying it's necessarily correct, but it does seem well formed, and LLMs only undermine it in a very weak sense (so far?). To defend the conclusion itself I would have to know a whole lot more about how he estimated information content (needed and available).