So I had to create a whole new label for this one. It took hours of work and effort, and I didn't even get paid. (Just kidding. It takes two seconds to write it in that little label box thingy.)
Here's what we know about Screenslaver from Incredibles 2: He hypnotizes people through the TV. He lives among the trash under an overpass. He has his own helicopter. He is way scarier than Syndrome. And he might not be who we think he is.

Other than that, we know jack shit about this badass-looking villain. However, I think it's safe to assume that his identity isn't just "some random guy from the street." Screenslaver is somebody. Who that somebody is? Remains to be seen.
Since there are multiple novelizations for the movie already floating around that spoil the entire damn thing, and since people have been kind enough to upload videos of themselves reading said novelizations and spoiling everything on YouTube, anybody could easily go find out who Screenslaver is right now. (Unfortunately.) But I'm not that kind of gal. I have self-control. And I prefer to guess. Guessing is fun.
Here are some possibilities.