The way it works for me at least is I can fit a huge amount of context in my head. This works because the text is utterly irrelevant and gets discarded immediately.

Instead, my brain parses code into something like an AST which then is represented as a spatial graph. I model the program as a logical structure instead of a textual one. When you look past the language, you can work on the program. The two are utterly disjoint.

I think LLMs fail at software because they're focused on text and can't build a mental model of the program logic. It take a huge amount of effort and brainpower to truly architect something and understand large swathes of the system. LLMs just don't have that type of abstract reasoning.