LOVE IT!
Of course, this is one guy and his one kid, so I can't judge whether it was appropriate or not. But it's not an automatic "horrible parenting" in my mind, no way.
I think the post that kid made was way out of line, and clearly this has been an ongoing issue. If it were me, I'd sell the computer rather than destroying it (though if I did, it would be with a sword not a gun, lol), and then use that money as some kind of teaching tool that was meaningful and specific to that child.
This is an endemic problem in the US right now. It started with my generation (Generation X) who were raised by the Hippie generation. My parent's generation taught us (whether they meant to or not) all of the values of the 60s ... "Don't trust anyone over 30," authority is meaningless and something to be disdained, showing respect to others (especially elders) is not necessary, if you are "passionate" about something, it's okay to do it no matter what, working hard is pointless if you can get what you want by an easier way, etc. etc. etc. (I'm speaking in generalities about society as a whole here, not specific parents. My parents didn't teach me most of those things, yet they are ingrained in me all the same).
Generation X has an ingrained disdain for authority, an entitlement mentality, and a general lack of respect for others. The children of Generation X (the early portion of which are in their teens now) are even worse in all these aspects. Society as a whole is in a LOT of trouble if parents don't start teaching children respect and responsibility.