Dude got tired of maths, moved to a cabin in the woods to live by himself. Part of the woods he lived in was destroyed by loggers and road builders. He got mad and started a bombing campaign against people who he views destroy nature.
He also went full reactionary sexist and homophobe. Plus bombed random people like a guy selling computers.
I really dislike the way he’s venerated by some. There are actual revolutionaries with cohesive ideologies that properly critique society and direct anger at systemic problems. This guy was just mad things were changing.
He definitely had some problematic opinions. Namely he thought that modern feminist and gay rights type movements were distracting from bigger problems. Though he did actually get that ideological idea from Marx who theorised that the owner class distracts the worker class with disputes over social rights of marginalised peoples to distract from the bigger problem in society (which marx viewed as the owner classes monopoly on ownership of means of production, while Kaczynski viewed it as techno-industrial society which removes people far from their natural behaviour (self reliance and sustenance) and destroys the nature which makes it possible.)
Not sure that qualifies him as a “full on reactionary” though. And I’m not sure I agree with your dismissal of his writings as “just mad things were changing”. They’re quite thorough and rigorous. He spent a couple decades writing multiple theoretical works to back up his views. We had an entire class on them at the masters level in social theory.
Marx doesn’t come down against rights though, Ted did. He specifically wrote about how women should be subservient to men, it’s vile stuff.