The ideal answer is that the person is really interested in the subject they are studying and want to know a lot more.
The honest answer is that society forces them to go to university as the next step towards a high paying job. The fact that it's also a chance to PARTY is probably also significant!
For the person whose only motivation is the latter, then the logic of cheating is overwhelming; they don't really believe that they need the stuff they are being taught, so why bother to play nicely?
The AI challenge, on top of the pandemic's revelation that an awful lot can be done on line, is raising all these hard questions which nobody wants to face. However to some extent it is merely clarifying the questions which were already being raised about the degree to which a university education has become a weapon in the arms race of getting the first job. Once you start to see the university industry as arms salesmen in a war, it's a lot easier to disregard their self serving claims to be making a meaningful contribution to our culture. Of course SOME are doing things of value - especially in STEM - but overall?
Perhaps the answer is for major companies to announce that they are going to recruit high school graduates with good SATs results for in house apprenticeships that will lead to management. Unfortunately most seem to be continuing to use a degree as the first jump for candidates to get over...