Well, they have a name. They have structure (of sorts). They have a common machine language it seems. Might as well have a logo. If anything, if their logo is (in)famous across the galaxy and they stamp their logo on all their communication, it may demoralize their opposition and have them assimilate faster and easier, making Borg job easier.It's weird they'd have one, but that looks like it could be some type of interface rather than logo.