You can save time at the cost of headaches, or you can save headaches at the cost of time. You cannot save both time and headaches, you can at most defer the time and the headaches until the next time you have to touch the code, but the time doubles and the headaches triple.
There’s one valid use-case for LLMs: when you have writer’s block, it can help to have something resembling an end product instead of a blank page. Sadly, this doesn’t really work for programming, because incorrect code is simply worse than no code at all. Every line of code is a potential bug and every line of incorrect code is a guaranteed bug.
I use an LLM with great success to write bad fanfiction though.