Cognitive offload is nothing new, if you've been around for even a little while you've likely personally experienced it.
just like a muscle will atrophy from disuse skills and cognitive assets, once offloaded, will similarly atrophy. People don't memorize phone numbers, gps gets you where you want to go, your IDE seamlessly helps you along so much you could never code in a text editor, your TI-89 will do most of your math homework, as a manager you direct people to do work and no longer do the work yourself.
We of course never really lower our absolute cognitive load by much, just shift it. each of those points has it's own knowledge base that is needed to use it but sometimes we lose general skills in favor of esoteric skills.
While I may now possess esoteric skills in operating my GPS, setting way-points, saving locations, entering coordinates, if I use it a lot I find I need it to get back to the hotel from just a few miles away even if I've driven the route multiple times. I'm offloading learning the route to the gps. My father on the other hand struggles to use one and if he's away he pays a lot of attention to where he's going and remembers routes better.
Am I dumber than him? with respect to operating the device certainly not but if we both drove separately to a new location and you took GPS from me once I got there I'd certainly look a lot dumber getting lost trying to get back without my mental crutch. I didn't have to remember the route, so I didn't. I offloaded that to the machine, and some people offload a LOT, pretty sure nobody ever drove into a lake because a paper map told them to.
Modern AI is only interesting insofar as it subsumes tasks that until now we would consider fundamental. Reading, writing, basic comprehension. If you let it, AI will take over these things and spoon feed you all you want. Your cognitive abilities in those areas will atrophy and you will be less cognizant of task elements where you've offloaded mental workload to the AI.
And we'll absolutely see more of this, people who are a wiz at using AI, know every app, get things done by reflex. but never learned or completely forgot how to do basic shit, like read a paper, order a salad off a menu in-person or book a flight and it'll be both funny and sad when it happens.