Cars qualitatively opened up something that humans could never do before.

Not really, we explored almost the entire world on foot and horseback. Cars and trains "just" make it easier.

A million lines of LLM slop?

As they say, quantity has a quality all its own. Over the last few years I was working on a side project that needed a lot of tedious logic of the form "if X then Y, unless both A and B, in which case either P or Q depending on the phase of the moon". I gave Claude the problem, it independently came up with a nearly identical architecture to what I had already built, then tore through all the scenarios and produced thousands of unit tests along with validation and fuzzing scripts. The code isn't terribly elegant, and was never going to be. But it works and it's shipping, and that wouldn't have happened anytime soon without AI.