There's a strong misunderstanding going on here of what "authorial control" means, though. Anything you can do in a game, even a free-form game, is taking place

There's a strong misunderstanding going on here of what "authorial control" means, though. Anything you can do in a game, even a free-form game, is taking place within a system of rules set down by the game's designers and programmers. Games are interactive, and obviously accept input from the player, but they are as strongly, and really, as exclusively authored as any other medium. Ebert comes at it entirely from a film point of view -- video game players can (depending on the game) have control of the camera, of the movements and decisions and dialog choices of the protagonist, or even in some cases, control of the narrative! Every movement in a game, though, is restricted (or it might be better to say, "allowed for" or "enabled"), by the designers. Unless it is a poorly constructed game, you can't go walking off out of the game's predetermined accessible areas. Every line of dialog was written by a writer, or recorded by a voice actor (or, if it uses some sort of procedurally generated speech system, is operating under rules built by a programmer and game designer). Some games are more forgiving of "emergent" moments than others -- having gameplay systems which are built to intersect and collide in unexpected ways -- but all of those underlying systems were designed and built with the purpose and expectation of creating interesting collisions. The problem is that Ebert is framing games like he'd frame a piece of serious film or literature -- defining authorial control in terms of narrative, or at least in terms of character, which is ridiculous. If Ebert ventured into a gallery space and encountered an interactive art installation which created some sort of projection which responded to his body movement, voice, and an artist-chosen soundtrack, would he declare that it inherently wasn't "art" because it wasn't a painting? I think he's confusing the presence of a protagonist and the use of filmic storytelling tools and cinematography for a classic narrative work, and then sees players diverting that narrative and shaping that narrative and tearing it apart, and decides that there can't be anything valid there. Narrative can be a great tool, or even a framework, to build into a game, but the rules of conventional narrative not what games are inherently about, and that makes them a misguided criteria by which to judge them.