Ranked 1st in the whole school, but can't get into SKY?

It sounds strange, doesn't it? In the past, even being ranked 20th in your high school was enough to get into SKY, but now even the top student might not make it. Even the student population has decreased significantly. Older generations seem to have a hard time understanding this.
Compared to before, the number of general high schools has increased significantly, and the number of students per grade has dropped from around 800 to around 200. In schools with fewer students, there are many cases where even being ranked 1st in the school isn't enough to get into SKY, let alone medical school or Seoul National University.
Of course, students from specialized high schools or general high schools in prestigious school districts still get in frequently.