He doesnt have much in common with the people mentioned in this article, except Breivik maybe, though i might be completely wrong since i havent read up on the Unabomber.
The first was at 9 months after bieng born, he got a bad case of the hives and was isolated from his family, with no visitors. This time is the most important time for newborns to bond with their parents and he was deprived of this. His treatments lasted over 8 months which affected him profoundly:
"His mother wrote in March 1943, "Baby home from hospital and is healthy but quite unresponsive after his experience"
The other was a psychology experiment he participated in while at Harvard which people believe fueled his anti-science views:
During Kaczynski’s sophomore year at Harvard, in 1959, he was recruited for a psychological experiment that, unbeknownst to him, would last three years. The experiment involved psychological torment and humiliation, a story I include in my book Mind Wars: Brain Research and the Military in the 21st Century.
The Harvard study aimed at psychic deconstruction by humiliating undergraduates and thereby causing them to experience severe stress
source: https://www.psychologytoday.com/blog/impromptu-man/201205/ha...
The Atlantic had a good story on the experiment as well: http://www.theatlantic.com/magazine/archive/2000/06/harvard-...
Notwithstanding his murderous behavior, Kaczynski's manifesto is absolutely worth reading. Though uneven, it contains some profound insights, many of which will resonate with anyone interested in social theory.
I wouldn't say it's "unusual" [2]
[0] http://maamodt.asp.radford.edu/Psyc%20405/serial%20killers/B...
[1] https://en.wikipedia.org/wiki/Andrew_Cunanan#Early_life
[2] http://www.examiner.com/article/22-serial-killers-with-high-...
I actually thought it was fairly common for mass killers (other than those whose mass killing is confined to a single mass casualty attack / killing spree), if for no other reason than not being smart makes it more likely that you get caught before your killing reaches the level of "mass".