I don't think I really agree with this. Steve has a ton of stage presence and keeps eye contact with the audience most of the time. Janick is out there performing the entire set as well. Adrian is the most reserved, while Dave is just having a jolly good time, most of the time.
Compare them to, say Blind Guardian for example. I adore that band, but their stage presence is severly lacking and their shows can be quite boring. Hansi is a good dude, but he never felt like a metal frontman; he has the energy of a high school teacher. Andre is mostly locked to his wah pedal and stares at his guitar. The only one who bring some energy into their shows is Marcus, the rhythm guitarist. Maiden is on another level compared to many other bands out there.