This could be complete bullshit because im not an expert but i sometimes think that we could have a future where without testing and nurturing peoples critical thinking skills we end up with people who dont know how to create a rational argument or assess information they are given for its accuracy and authenticity, or to know when they are being deceived by malicious actors.

English writing assignments as simple as a book report require you to take different views and angles on something to understand it better and the nuances of the whole, but tell a LLM to write it for you and you are not developing that part of your own mind where you may learn to do things like see the whole story above the individual events noise, see things from others perspective/feelings and understand alternate world views. These are critical for having empathy for others and understanding the world around you.
And that is just one small example i came up with.