Social media presence as in having accounts in your name with you being visible in the profile picture in mainstream sites (Anything Meta, Twitter, Snapchat, Tiktok…). I don’t consider anynounmous accounts on Lemmy, Reddit, Kbin relevant to the scope of this question.
Yeah. You are often left out of group activities, your friends don’t chat with you as often (not talking about close friends, but more about those buddies you go out with once in a while), you’re left out of local communities (there were very few people from my country on Reddit, it’s even less on Lemmy).