Are calculators making you less able to do basic math in your head?
Do anti-lock brakes and lane assist make you less able to pay attention to the road?
Does religion or any other similar belief system (for example, those of the far-left or far-right) make it harder for people to think critically?
Well, yes. Or more precisely, they allow people who can't do those things well anyway to get by. The average American adult functions at a middle school level academically. (And I'm pretty sure socially, too.)
Take away all of that assistance, and we're not going to make everyone smarter. The wetware in our skulls evolved to solve the problems we had 10,000 years ago. We've done amazingly well with better education methods and better nutrition and better healthcare. But the average person today is simply not capable of handling the average problems of today.
The bigger question is whether we will use GPT as helpful assistance, to enable people to do more than they otherwise would be capable of? Or will we simply use it as this century's opiate of the masses.