I don't think chatgpt created the problem, although it may contribute to it.
Here's a hypothesis:
The problem is that thinking analytically, rigorously, is hard work. People do not often seem to come to it by accident. It's something we have learned to do, and schools/teachers are one of many mechanisms we have used to culturally transmit these skills. Until (pick a date -- 1950, say) it was assisted by the fact that one of the most widespread forms of entertainment was reading. Yes, even by then movies were a thing, but most people couldn't afford to go to a movie every night, and they were limited to what was currently showing. So most people in western countries, where literacy was high, spent a fair amount of time reading. Reading, by its nature, tends to focus the mind. You learn to spend long periods ingesting and contemplating information.
We also taught writing -- and we still do -- but it benefits hugely from all that time spent reading. It is much easier to learn to write if you read a lot. And writing further develops your thinking skills.
The modern era has given us wonderful technologies, but there is a lot of evidence that people are struggling to focus in the way we once did. People read less, write less, and spend more time on other media. I'm not slagging on film or games or cell phones -- conceivably, other useful skills are imparted, and people enjoy them. But our ability to focus seems to be declining. Chatgpt is just another time-saver that makes it easier to avoid learning critical thinking skills.
It's not impossible that teachers will find a way to compensate. I think there are some things working against that: 1) we don't fund schools in a way that is going to allow them to spend additional time per student. 2) societal expectations seem to be that teachers magically pour knowledge into children, rather than learning, fundamentally, being something the child has to do, and which requires a large parental investment. 3) a lot of what lead to focus in the first place didn't come from the schools, but from the social environment -- i.e., reading was the most practical source of entertainment -- and so we are expecting schools to compensate for a problem they didn't create and for which we may have no totally satisfactory solution.
I suspect that's only part of it. The pace of life is very different than it once was. Even an illiterate in 1800 probably worked on fewer things per day and perhaps had more chances to focus. But that's sheer speculation.