Both Iago and Othello have character traits which are still fascinating to a modern audience. Parallels can still be drawn with figures in popular culture today who act upon the sort of qualities which also drove Othello and Iago.
Othello is a well-respected and adept military tactician. He is unable, however, to balance his military skill and insight with equal perception and understanding of matters of the heart. His Achilles' heel is his gnawing self-doubt regarding his social prowess and it is this weakness that Iago manipulates.
Iago is admired and abhorred for his clever machinations that bring down all of the vulnerable characters in the play. He too has an inner insecurity and weakness regarding his own social acceptance, but chooses to mask his inferiority with his superior planning and cruel revenge.
Put simply,both characters have the same insecurities as people today.