Myspace died because it tried to become more like Facebook rather than further differentiating itself from it.
Facebook allowed me to reconnect with family and acquaintances I had never encountered online before. Messaging became the normal way to let someone know evening plans, or to send an interesting link to a specific person. I can't even estimate the number of people I'd deduced had met their demise when I'd see the same face three or four times when checking my feed. Facebook was (is) about where you go/went to school, where you worked, and who you really knew IRL.
Myspace was the virtual equivalent of putting on an album, and leaving some CDs and books on a table in an unlocked room alongside a note reading "BRB, make yourself at home." It was where people cataloged and displayed their interests, hobbies and favorite entertainers and celebrities. And while ranking your "Top 8" friends was surely a real thing most people I knew used their top 8 to recommend their favorite musical artists, obscure interests, and even other favorite websites.
Facebook became worse in the absence of Myspace as people began posting more things on Facebook that would have been posted on Myspace previously. Facebook is/was about presenting yourself online as you wanted to be seen by your family and associates. Myspace was about presenting your interests online to be seen by friends and acquaintances you wanted to let know what you were actually into.