I think plato was right, just not in the way we understand it right now. Maybe even not as he meant it, which I would need to read some of his works for.

I think the synthesis of our points is "it takes out the need of certain ways of thinking and frees up capacity which can be employed elsewere."

Example: i think it is clear that in the past, every human knew how to hunt or which berries to collect for example, more or less. Otherwise they were dead. We lost that skill and in the woods, we would probably have a bad time.

I think the written word abstracted thinking, not killed it. Where there was sounds there now are syllables. Think about it. We (or its what i assume) think in written words, not in sounds. This probably changed how we perceive sound and words and maybe we lost some depth in that field.

Same goes for chatbots who do our critical thinking now. It would have dire consequences indeed. But otherwise, if employed correctly, we could build something (and we lilely will arrive there at some point) that frees up brainpower. But it will likely be capitalism that needs to go to free out braincapacity since that is where we are constantly under threat.

Anyhow, I hope this sheds some light on how i view this.