I'll take your word for it that that's true (not on Tin Tok). I'm glad to see it.
It's definitely happened. The biggest example that comes to mind has to be Lil Nas X's "Old Town Road". I guess he was 20 when it blew up, so not a teenager, but close enough. https://en.wikipedia.org/wiki/Old_Town_Road
Justin Bieber? Pre TikTok but still.
Don't forget that that can also be a backported success story