The core issue is that it takes a large amount of effort to even assess this, because LLM generated code looks good superficially.
It is said that static FP languages make it hard to implement something if you don't really understand what you are implementing. Dynamically typed languages makes it easier to implement something when you don't fully understand what you are implementing.
LLMs takes this to another level when it enables one to implement something with zero understanding of what they are implementing.