In my experience, in college I learned the theoretical and on the job I learned the practical.

For example, I learned how to conjugate verbs in foreign languages, and algorithms with O(n) vs O(log n) in computer science.

Then later in a foriegn country I expanded my my vocabulary. On the job, I learned about version control, how to read other people's code and how to fix bugs.

Most students in CS are hired prior to graduation. On both sides the savings of skipping that last semester are marginal, and on the student side there's a nontrivial opportunity cost. 6 months of: studying whatever problem you want with the background you need to maybe solve it, networking, building code/ideas you own, socializing with a purpose (courting) or for fun, or, if you're smart, a bit of all 3.

There's a discrete jump in the career value of the education between not quite finishing a degree and graduating. It's not because there's some super important final semester that's worth much more than any of the previous ones. It's no doubt because it signals some quality like conscientiousness, or perhaps is just easier for an employer to evaluate the meaning of.

Which is why hiring college grads right before they graduate is the best deal! You get a discount hire who will have a hard time getting other jobs!