“[Unsubscribe]” is framed as a show about artists who “engage questions of e-identity formation and social interactions that play out in our imaginations,” exploring the avatars we embody online and offline. It’d be shopworn territory if it weren’t a red herring. The exhibition, set up in a house gallery in Little Haiti, one of Miami’s most rapidly gentrifying neighborhoods, mines the internet not simply as a place where real and unreal blur but as a space populated with the same entrenched prejudices that fuel every other system.