I agree with @MWolf that the Ivy Achievement article is really bad.
Their search criteria looked for people who worked in the San Francisco Bay Area at a number of well known firms, such as Apple, Microsoft, Sales Force, Google, etc.
Here is the main problem with that search: some of the most talented software people don’t work for these companies. They will instead be working on a startup that they hope will make it big, or they will be working for hedge funds on the East Coast for really big money. A lot of these kids come from places like MIT, or Harvard, or Michigan, which is why they are under-ranked relative to what you would expect.