axh

Every breath you take, every keystroke you make, he’ll be watching you!

Yes, but only after learning about types of objects and types of visualisations on thousands of examples. For example they see people (parents, siblings and others), they see drawings of people in books, they see people as toy figurines, that way they learn concepts like drawing and sculpting, they can recognise that concept and copy it on different ideas (for example they can imagine how crocodile looks like even though they only see it in a book). That actually is similar to AI image generation, where you can add images of a person (only photos) and examples of an art style. And AI will be able to generate images of that person using that art style (with various success).

No large training sets? The baby is updating their training data set every second with new sounds, images and other sensory inputs (smell, touch). Current data centers would be overwhelmed with the amount of data that one child processes every day.

Your browser wouldn’t be able to load any js based sites

You could make a browser capable of loading both, and I think it already happened. The problem is, that a browser supporting more languages than necessary, was never successful enough to get mass adoption and on the internet you need mass adoption to survive.