"For all of the good the internet can do, it can be a dark place and parents would be wise to monitor the activity of their children online," he said.
He's right, but this isn't "the web's fault". This kid was fucking broken. End of story. Offer me $100M to kill an innocent and I'm going to say no. Especially to a stranger with no proven resources to pay me. (Make the person someone evil and the answer changes.)
There's only so far "But the internets!" is going to take you when trying to place blame with something like this.
"Happy slaves are the worst enemies of freedom." - Marie Von Ebner
"It was always the women, and above all the young ones, who were the most bigoted adherents of the Party, the swallowers of slogans, the amateur spies..." - Orwell