“The internet doesn’t turn people into assholes so much as it acts as a massive megaphone for existing ones, according to work by researchers at Aarhus University.-Tom McCay, “Online Trolls Actually Just Assholes All the Time, Study Finds.” Gizmodo. August 27, 2021.
I think there is a troll gravity online, where the megaphones of a few draw people into their troll orbit. And like gravity, there is a difference between super massive jackholes of trolldom, where galaxies of individuals revolve around them. On the other end, there are the asteroids and comets of trolldom, not there all the time, but occasionally, they fly in and are a spectacle. If you are going to have this kind of discussion, you probably need to develop a taxonomy of trolldom.
Also, the reason people behave differently online is because there is not a threat of physical violence. A grief troll online can just ask questions that offline would likely end in a beating.