people just text me to invite me to things. I don't want to be invited to parties where someone just invites everyone they know on Facebook.

if they want me there, they can ask me directly. My social life has not significantly changed since I quit Facebook.

if you have good friends, they will find you. if you don't.. why do you care about losing them?

Popular kids don’t care about that.

That’s a pretty glib stance. Plenty of people have difficulty finding a friend group and not everyone can be an island until they do (see the loneliness epidemic). Perhaps consider that there are other people with different life situations than yours for whom demanding individualized treatment does not work, and they may have much less choice about what technologies they have to use as a result.