You'll notice that there was virtually no griefing or trolling in old MMOs.
I call bullshit.
From 2001 till 2004 I played the oldest of the popular online MMOs; Ultima Online. Trolling occurred through excessive player killing, disruption of guild activities and dungeoneering plus people doing some honest mining. It was characteristic celebrated amongst perpetrators and adrenaline junkies but reviled amongst those wanting a less combative, PvE experience.
It was already on the decrease when I joined up thanks to the introduction of a non-combat realm. Nowadays a few thousand people yearning for the lawlessness of the old UO have founded their own free servers replicating the 'Wild West' culture.
Trolling isn't exclusive to new MMOs or modern forums, social media and so on. It was present in the early days of Usenet, the earliest chat rooms and IRC channels, and from the very first online games venturing beyond LAN and Intranet play.