Working in aerospace, code generation tools are indeed reviewed pretty thoroughly.
What do you mean "reviewing" throwaway tools and scripts? If you wrote them yourself, presumably you understand what they do?
I've also spent countless hours debugging throwaway scripts I wrote myself and which don't work exactly like I intended when I try them on test data.
If you have an LLM transform a big pile of structs, you plug them into your program and it will either compile or it won't.
All programmers write countless one-off throwaway scripts. I can't tell you how many times I've written scripts to generate boring boilerplate code.
How many hours do you spend reviewing such tools and their output? I'll bet anything it's just about zero.