It's not easy to be a junior, and we might be speaking with survivor bias, but most juniors don't end up in solid engineering teams, they are merely developers that are much cheaper and from whom you expect much less, but more often than not they are borderline left learning and figuring out things on their own. They need to luck some senior member that will nurture them and not just give them low quality work (which I admit I have done too when I had myself lots of pressure to deliver my own stuff).

Even in less desperate teams, as productivity grows with AI (mine does, even if I don't author code with it it's tremendous help in just navigating repos and connecting the dots, it saves me so much time...) the reviewing pressure increases too, and with that fatigue.

It does matter, because it's a worthwhile investment of my time to deeply review, understand, and provide feedback for the work of a junior engineer on my team. That human being can learn and grow.

It is not a worthwhile use of my time to similarly "coach" LLM slop.

The classic challenge with junior engineers is that helping them ship something is often more work than just doing it yourself. I'm willing to do that extra work for a human.