On instagram, which I only use these days to follow friends who are on there, the most frequent "notification" is from obvious spam (presumably phishing) accounts. Meta has thus far been unable to stem the never-ending flow.
Except these accounts are all brand new. I don't know anyone who's not on instagram in 2024 that will decide to sign up and follow me
If Instagram had a flag that said "don't let new accounts follow me", it would stop the spam dead.
