> free up more brain power for other newer or different things?

That's wildly speculative. So speculative, it cannot be taken serious as an argument. The brain is flexible, but not unlimited. Quite a few functions seem to prefer a specific part of the brain. In fact, I don't know of any that is free floating, but that might be because it's hard to find.

But what the brain above all requires is training. Without it, all that power is laid to waste. You can't learn a new language without actually learning it, nor can you do something new without actual training. You can't be intelligent without training your intelligence, and put real effort into it. Relying on a computer for the answers keeps you dumb. Use it, or lose it, as they say.

And what is that new thing that our brains are going to do? You don't know. And since you don't know, why throw it around like it will offset the harm that can come from using AI? Are you already that dependent on it?