There's nuance here though, LLM's actually do a better job of code that looks like it should work.

You get an unskilled junior in the mix, their code is obviously bad.

You get a semi decent LLM with a competent harness in there and you get a mix of code that works and code that nearly works.

There should be competent peer review either way, but the effort for each is potentially an order of magnitude different.

Then add on top that the LLM can churn them out way quicker than a junior could possibly achieve and you have a recipe for a huge review burden.