How would a lack of extracurriculars effect getting into an Ivy League college?

Everyone applying to the top schools has the highest grades in the hardest classes and extremely high test scores. They take fewer than 10% of them, and they need some way to figure out who the most promising students are. That's why they want to see activities - and one fantastic activity is better than joining everything out there. They're looking for students who did fantastic things and would have done them even if they weren't trying to get into a top college, just because they wanted to. Like publishing a novel, or doing original scientific research, or patenting an invention, or getting a record deal, or starring in a major movie. They're looking for passion, drive, motivation, ambition.