Also, if you're interviewing current university seniors, you're interviewing people whose CS education got hit hard by COVID. They probably spent the first two years of their college experience remote, then the next two years in hybrid sometimes-remote purgatory. It's a little understandable that they wouldn't have the strongest background.

In a lot of cases those areas are also covered solely by electives, so unless the student was lucky enough to take those classes, or they happen to spend their free time reading about these topics, they won't know them.