Assuming it’s true, a twenty year old in the year 2024 having zero social media footprint? That’s pretty dubious. I taught in a public HS and unless the family was part of some austere religion, there’s just no way he wouldn’t be online. And the fact that he was perceived as a loner seems to make it even more likely that he’d be online. Doesn’t seem like he was out having fun with all his buddies. Super sus. But I bet they’ll find some profile for which he used some alias.