> work mentoring the AI strikes me as less valuable then the same time spent mentoring a junior developer

But where can you just "mentor" a junior? Hiring people is not so easy, especially not ones that are worth mentoring. Not every junior will be a willing, good recipient of mentoring, and that's if you manage to get one, given budget constraints and long lead times on hiring. And at best you end up with one or two; with parallel LLMs, you can have almost entire teams of people working for you.

I'm not arguing for replacing juniors - I worry about the same thing you do - but I can see why companies are so eager to use AI, especially smaller startups that don't have the budgets and manpower to hire people.

If a junior is not willing to learn and grow, there is no future for that person in the organization. "Forever junior" is not a valid job title. Better not hire someone that is not good enough than having to deal with the consequences, I learned from my past mistakes.