I do know that he specifically focuses on how technologies gradually advance so that we're forced to use them. He refers to this as "control" and describes how technologies don't seem harmful independently, but as each technology forces itself upon us, the combination becomes more and more controlling, until we're completely controlled by the whole. It's as if technology is slowly chipping away at the foundation of freedom through compromise, or something like that.
Now, what I said was that he focuses on the controlling aspect of what were at first seemingly innocent technologies that were absolutely beneficial, but he doesn't see the increase in freedom that the same technologies provide over the long term. Yes, there are stop lights, roads, licenses, and jobs are further away from home, forcing us to own cars—but at the same time, you can go anywhere you want within hours instead of days. Is it controlled? Yes. But even with the control, the total amount of freedom the individual has is now increased, because one is no longer confined to a small area.
Kaczynski uses the neighbor scenario—there are two neighbors, and one is more powerful than the other. This more powerful neighbor asks the other to give him land, to which the weak one says "no." So the powerful one offers a compromise where he only gets half of the land he had asked for. The weak neighbor can't refuse. This goes on and on until the powerful neighbor has all the land. My argument here is that while the powerful neighbor might be taking away land, the big picture is that the powerful neighbor is also offering the weak neighbor lots more land somewhere else. Yes, technology takes our traditional freedom (the already established plots of land), but simultaneously extends our freedom in new directions (new plots of land). Kaczynski only views freedom as something that can be subtracted but not added to.
Perhaps I understand his arguments incorrectly, but this is what I've gotten out of what I've read. If you don't agree, go ahead and explain what's wrong, but don't just make an empty claim like that.
Of course, you can reply that Kaczynski is stupidly ignoring the positive effects of these technologies and that he is wrong when he asserts that the things that they give us are not fundamental to human happiness. To argue this, you will have to make certain claims about human psychology. Obviously there are plenty of things that we enjoy but that could be removed from our lives without causing great harm to us (Skyrim, for example). There are other things that are integral to our happiness (the love and respect of our family, for example). Kaczynski is arguing that technology attacks things in the second category while giving us lots of things in the first category. His underlying argument is that modern individuals have, through adoption of advanced technology, lost touch with fundamental sources of happiness. The setting in which to substantively debate Kaczynski is the setting of psychology, I think: what really makes us happy?