While it seems evident that increased interaction in the digital realm can only lead to increased agency, some paths to expanding interaction decrease the individual's agency. While theorists ranging from Vannevar Bush to Engelbart have dreamt of the possibility of augmenting the human mind through interaction with computers, many others saw digital media and the interactivity it provided as means for increased control.
Engelbart and Licklider, among others, dreamt of augmenting human intelligence, rather than merely assisting it, leading to a higher functioning state for both human and machine. The key to this idea was setting up symbiotic interaction between the human and the computer, each providing that which it does best. It is the very interaction between the mind and the computer that creates something greater than the sum of the two. Other types of human-computer interaction is possible, such as using the computer as a glorified calculator, but this would only speed up the process without augmenting the human mind, leading to better ideas.
Many people have conceded that interaction does not have be equal, it is in fact usually is quite unequal. In online newspaper, even though readers can write letters to the editor, post comments, etc., the bulk of the transmission of ideas is from the newspaper to the reader. In traditional performance, there is interaction between the audience and the performers, but the performers are generally in the role of dispensing the ideas, while the audience can mostly react with approval or disapproval, rather than directly contributing new ideas.
In many of the U.S. military's grand computer projects, unequal interaction is the central idea to allow for greater and more centralized command and control. The U.S. military (whose money provided for the vast majority of the computer industry until the 70's or 80's) drove computer research in order to get as much information as far up the chain of command as possible while allowing the commanders to directly control as much of the military as possible in a centralized manner.
In Operation Igloo White during the Viet Nam War, for example, they created vast interactive networks where the role of the almost everyone was to provide info to, and receive orders from the commanders. They were interacting with more people, more information, more ways of grasping data, but in the end this whole system served to take away independent agency, and place it more firmly in the hands of the higher ranking officers. "It was the perfect fantasy of the closed world of computerized and centralized command and control."
Had such people as those who commanded Operation Igloo White had direct control over the direction of computer research, digital media today would be about centralizing control rather than augmenting an individual's intellect. Such commanders where extremely suspicious of the ARPAnet, though impressed by the level of interaction it provided, because it allowed military personnel to talk to each other with their commander knowing.
This demonstrates that the nature of interaction in a given medium can be largely determined those who create it and their ideas about what it should foster. The central figures responsible for creating the internet and computers as we know them thought that augmentation of intellect through increased interaction was the central idea. This is why digital media provide interaction that fosters agency for individuals.