Please explain to me why people like the Jonas Brothers?

Not my type of music. Whatever happened to bands like Aeromith, Black Sabbath, Bon Jovi, Guns and Roses, Iron Maiden, AC/DC? I wish I grew up in the 80s. Great music back then with music and lyrics that everyone can relate to, not just tween girls. But I give them credit for somehow winning the hearts of millions with mediocre at best songs and really whiny girly voices.