LoC isn’t a super helpful metric so I think the better question is why is the headline using it. I can say I’ve personally created about 200k LoC code in the last 5 years and most of that has some value. But it really doesn’t say might about how much value or really anything else meaningful.

They're probably mentioning the size of the code base as an indicator for how difficult it is for an LLM to understand where and how to make changes.