You're fully capable of googling it yourself so I assume there's another reason behind your question but it generally refers to any self fancied Internet activist who thinks whining, complaining or arguing on the Internet is enough to affect serious social change. Their arguments frequently include shallow reasoning, obvious bias or hypocrisy.
I just didn't want to go with what I assumed you meant. anted to make sure I wasn't putting words in your mouth. Seeing as you did mean it in it's common pejorative sense we can move on.
SJW isn't a group. You set them opposite them to 4chan. 4chan is pretty easily defined as people who post there. Even #Gamergate, the amorphous blob that it is, is more definable. At least some people use the hashtag to identify themselves. There is not really a group that self defines as SJW. SJW is a pejorative term that was created by the same circles as those that identify as Gamergaters. It is a word they use to define their perceived enemy. You can go to 8chan or KiA and see how it is used.
How does it make sense to say:
4chan and SJWs both thrive off of attention, positive or negative, and the only way to remove them from the conversation is to ignore them and divert the attention to more constructive avenues of discussion.
You are setting a group against it's own self defined boogeyman. It doesn't make sense. You are creating a group to disparage.
Lets look at your definition:
it generally refers to any self fancied Internet activist who thinks whining, complaining or arguing on the Internet is enough to affect serious social change. Their arguments frequently include shallow reasoning, obvious bias or hypocrisy.
Do you really think that there is a large group of people who think that they can effect social change by
whining? This definition is so general, so broad and so contemptible that it can be levied against almost any group one disagrees with. It's a nothing term. An empty vessel that people just fill with bile and lob across the internet at people.
And what exactly do you and your female friends think can be done to correct 4chan's evil ways? (pardon my snark, I'm trying to illustrate the absurdity of the situation). Are you aware who these people are? Ignoring them is absolutely the worst thing you can do to them.
Social change is pretty common. Historically the answer to your question is to constantly create awareness of the issue, humanize the issue, and create constant social pressure. Such things can take decades but they can and do happen.