Overall, technology can be trusted. There will always be the odd failure or glitch, but we're getting good at making things that work. Except Windows, of course.
On the other hand, you should trust the people providing the technology about as far as you can throw them. Plus, there will always be thieves, modifying that tech for their own purposes. Card readers at the ATM for example.
Not sure what you refer to. The dot com collapse? But that wasn't the fault of technology - that was from the stupidity of investors going crazy over business "opportunities" that actually had little to do with technology.
We are for the most part responsible for our actions. While some bad behavior/actions are due to psychological trauma and abuse like that, most of the time people commit acts and they use technology that are detrimental to others like hacking, nuclear, killings people by the use of biological weapon of mass destruction etc.