IG/ Threads notifications

Hi! I don’t currently have a threads account but had a general question… what does it mean if instagram keeps notifying me everyday (it literally sends me a daily notification around midnight) that “someone (specific IG username) and x others are on Threads, see what they’re saying”

Is there any way I can stop receiving those notifications? And if anyone knows, why is it that one specific person’s username considering we don’t even talk on insta and not other people who i talk to regularly (they’re also on threads) ?

If anyone has any insights, would appreciate it! Thanks!