If the students are genuinely curious, there is nothing to stop them learning about pretty much any topic in CS - really. There are few university subjects where the entire syllabus is freely available online in almost every format imaginable the way CS often is, and very often the computer you already have works just fine to learn it on.
(Hurrey for Termux)
Network building, external proof of ability to work, and a place (and just as important - a time) to translate who you are into who you want to be.
These were always the reasons, the rest you learn on the job.
It's not that you have to learn everything on your own though, it's that if you enter a program without having some understanding of the basics, you're going to have to pay to take a bunch of remedial classes.
It'd be like going for a mathematics degree when the highest class you took in high school was algebra, where the normal degree students would be starting with Calc 3 or Differential Equations. You might be ok in the major or you might not, but you don't even know enough to start on the path at that point.
I'm a programmer now, but I don't think finishing the CS course would've helped much with that.
Lack of understanding coming into the courses causes issues, when I started we had to delay things because some students hadn't encountered matrixes and the maths around them.
So sure, they can teach these things but it adds to what they already are trying to teach. A lowered base means less of the advanced content can be taught.
It’s kinda shitty, but for a long time PC gaming as a gateway drug for young kids let universities just assume a fat pipeline of already-computer-savvy applicants.
But that's not what they are taught now. They are taught to use social media and cloud services, which is completely useless since they figured this out themselves already.
The education system here just keeps them early in a consumer mind state. It has absolutely no ambition and is just a race to the bottom.
I learned CS ~20 years ago and it was mostly the same. Half of the first year is people that are vaguely interested in computers, video games, or heard it was a good way to make money, and didn't really have any real skills going into it.
It is somewhat different now, because there are students that think they are good with technology but really have no idea how things work, they just think they know because they are slightly better than their peers at using phones and tablets.