I was thinking and there might be a method to Billie's social media madness.
Despite how he presents himself at times, Billie is a pretty smart cookie and is probably more tech savvy than we give him credit for. I'm sure he knows that when he posts things, people will start spreading it around right away and it will continue to exist whether he deletes it or not. Maybe this is why he deletes his more "controversial" stories and posts on Instagram after a few minutes. He knows fans will repost it and people will see it, so deleting it saves him the trouble of being harassed by trolls. Most trolls aren't going to go after fan accounts or people just sharing his posts, so it's safe for them, just not Billie himself. Plus it's fun for fans and contributes to the sense of community. So it's really a win-win.
Whether or not this is Billie's actual motivation behind deleting his posts all the time is unknowable, but I just thought that was an interesting idea.