Yep exactly, but I think it's not just social media, it's there regardless and social media just provides a more convenient forum and a way to spread the vitriol more rapidly.
Your last paragraph is spot on. Those vitriol vomiters are often doing exactly what they perceive others to be doing to them, and yet they think it's legit for them and not for the others. As Bozz and Coloneljethro say in comments here...it's often deserved and brough on by their own actions.
That's my view on social media as well. And in some cases they're probably attempting to feel powerful "telling it like it is" because there is no immediate danger of getting punched in the face.
Indeed...but everyone is locatable. 😈🔨
LoL XD so not worth the effort though.