my sister says my niece, who’s 17, doesn’t any of the big social media platforms with her friends...I don’t know what they’re on now but they almost never use email, fb or twitter.
Teens I know (primarily boys) are using Instagram and Discord.
My son is 15, my daughter is 18. Both of them are big Discord users (they even have me using it). When I asked them about Facebook/Twitter, my son said they were for “older people”. lol