That's what LLMs can help with. With writing code for legacy code bases that don't have 3000 copies of the same tutorial in the first 3 pages of search results

That's what LLMs can help with. With writing code for legacy code bases that don't have 3000 copies of the same tutorial in the first 3 pages of search results... they help less. Note that most people claiming > 2x improvement are doing new code from scratch.