The worse part is reading a PR, and catching a reintroduced bug that was fixed a few commit ago. The first time i almost lost my cool at work and said a negative thing to a coworker.
This would be my advice to juniors (and i mean basically: devs who don't yet understand the underlying business/architecture): use the AI to explain how stuff work, generate basic functions maybe, but write code logic/algorithm yourself until you are sure you understand what you're doing and why. Work and reflect on the data structures by yourself, even if generated by the AI, and ask for alternatives. Always ask for alternatives, it helps understanding. You might not see huge productivity gains from AI, but you will improve first, and then productivity will improve very fast, from your brain first, then from AI.