These are “all over” a certainly, highly insular, and specifically-meme oriented corner of the internet. Being a world wide web user since the mid-90s and never a 4chan user, I can tell you, at least anecdotally, that “I” don’t know the names of any of these 4chan characters, and neither do any of my (entirely too online) irl friends. Shit, I hadn’t even heard the term wojack until a couple of years ago.