I'm a 14 year old girl, and I don't think depression = Billie Eilish. Because it's NOT Billie Eilish.
Depression is an actual mental illness that isn't fake or a joke. Lots of people suffer from it, and some people even k*ll themselves or cut themselves because they have it so severely. They might have trouble sleeping, eating, move slowly, and lots of negative thoughts, etc. It's not "cute" or "quirky." It's something you don't want to have. It's not a cool aesthetic, it's just sad.
Billie Eilish is just a white edgy 18-year old singer with a soft voice. They aren't the same thing. And I don't even listen to Billie.