There is no free lunch, if you use writing to "scaffold" your learning, you trade learning speed for a limited "neural pathways" budget that could connect two useful topics. And when you stop practicing your writing (or coding, as reported by some people who stopped coding due to AI) you feel that you are getting dumber. Since you scaffolded your knowledge of a topic with writing or coding, rather than doing the difficult work of learning it from more pervasive conceptions.
The best thing AI taught us is to not tie your knowledge to some specific task. It's overly reactionary to recommended task/action based education (even from an AI) in response to AI.