> because nobody needs mediocre engineers anymore.

This is giving too much credit to LLM. I think LLMs are great and it is incredibly useful both in personal and professional settings. However, it exist on a separate plane than human workers in the tools category.

Sooner or later, people will find out that LLMs only overlaps with existing human hierarchy (e.g. junior dev X%, senior dev Y%, etc), but almost never 100%. If it was 100% to a certain position, you are probably using the humans wrong to begin with there - since humans have one of the most priced thing that I don't see an single ounce out of LLMs: initiative