I don't understand how people who've actually used a modern coding agent, or know anything about them, can still be asking this question.
The most basic feature of LLMs is that they predict tokens based on their training data and input (context window.) But "predicting tokens" is not the same thing as copying snippets. None of this would work nearly as well if what they were doing was copying snippets.
And even if this were a question worth studying, the article's approach doesn't in any way help answer the question, because apparently the goal wasn't in fact to answer that question but rather to create a language that would be intrinsically difficult for LLMs. It'd also be pretty difficult for humans. That's what obfuscation does.
This would be better if it were just framed as a fun exercise, like any other obfuscated language, not as having some real purpose.