Yeah the argument is that there is a poverty of stimulus (not enough training data) in the case of children. The same doesn’t apply to ML models which need an abundance of stimulus.
There was some linguist (Deb Roy?) who videotaped his children growing up. One of his observations was that every learned syllable etc. was tied to observing it as a stimulus and trying to imitate it. Now it is true, children are pretty good learners, they can often learn something the first time they see it, but actually I have seen some LLM stuff about "instant learning" - e.g. the training is only done with one pass over the material. https://www.fast.ai/posts/2023-09-04-learning-jumps/
This is an interesting connection. If I had to guess, the Chomskyist response would be to say, yes but this only applies to LLMs that have been pre-trained already (i.e. have structures in place needed to understand language in general). I think a Chomskyist would say that language learning is precisely like fine-tuning and not the pre-training of foundation models.