A relatively old critique of technology is that technology dehumanizes us. Ellul articulated this well, but so do the existential critics of technology, like Marcel (Man Against Mass Society) and Marcuse (One-Dimensional Man). This dehumanizing takes a number of different forms:
1. Technology takes away our ability to choose. Someone might argue that we always have a choice, even if it is only the choice to drop out or to die (Sartre). Of course, the issue of choice is a difficult one. Right-wing politics claims that it is trying to get the government off our backs -- give us back freedom of choice. But is this really is freedom of choice. Or there is freedom for the rich, but not the poor?
Now, technology can have that right-wing political version of freedom. It is the freedom to control your own destiny, without asking what that destiny should be. It is, in effect, maximizing practical (means/ends) reason at the expense of the ability to reason about the goal. With a car, you have freedom to go anywhere -- as long as there is a road. You can choose anything, as long as it is off the menu. Any ice cream, as long as it is vanilla. So, there is a sense that our way is cleared to choose the things that technology has already admitted is a legitimate choice. Anything else does not compute.
2. Ellul argues that technology, in the fact that it is not natural, obeys different imperatives than the natural world. It means that it dehumanizes us by tearing us out of our home, and putting us into a foreign place. We have artificial everything, from grass to food to entertainment, and we have come to mistake these for the real thing. In fact, if we ever encounter the real thing, it can sometimes be disappointing. Sitting by a river in Kenya watching hippos can be a very boring thing, because they do not come out of the river on command like at Disneyland. You have to drive around the savannah, unlike at the zoo, where nature comes to you.
It means that we are estranged from what it is to be human, in that we get a false picture of the world in which we live. The only way this critique can work is if we assume that humans have two different ways of satisfying their needs, or at least, one way which really satisfies them and one way which only seems to. That means that we have to identify human needs. Ellul's criterion is that the means to satisfy needs must not restrict our freedom in the future. We must have freedom at the end of the technique, not just at the beginning.
3. One way that technology can take away individuality is by keeping a check on everyone. The Big Brother image, and the Thought Police from 1984 are familiar images. Can they happen?
The problem is that technology (particularly technology that requires corporate power and investment) tend to centralize the power in the hands of those at the top. This means that if you are an environmentalist who wants to protest against some oil company, your access to information will often be limited by those in power, like the friends of the oil companies. Expression, therefore, is limited.