This is from the very curmudgeonly Neil Postman, giving a talk in 1998 – at 5:53 in this video (which is part 4 of 7):

“And as for the term community, by the way, as it’s used on the internet, you should examine that very carefully, because it’s almost being used in the way opposite to the usual meaning of community. Most people, when they talk about they’re joining a community on the internet mean they’ve joined with people of similar interests. Now the more traditional meaning of the word community is that these are people who do not have the same interests, but they must negotiate and accommodate their differences for the sake of social harmony. So, there’s almost the opposite meaning.”