the feminist librarian reads

See back in Usenet, trolls didn’t harass a person, they tended to harass a group. They tended to bother a small community, crapping on things they could. You could blockfile them, but if you did that, you wouldn’t get rid of people responding to them. What’s more, this traffic represented a meaningful download – the burden was a technical one. So, bickering with a troll could mean 20-30 posts (which some readers couldn’t properly file or hide) that didn’t make any sense and just annoyed people. You didn’t feed the trolls not for your own sake or to discourage the troll (though that often worked out if everyone did), you avoided feeding the trolls because you didn’t want to make life harder for your community.