It is actually pretty simple, really. SJWs appeal to authority to make change. They bitch and whine to AMC, write letters to them, try to get people fired.
Lets say the issue is a trans Dr. Who, like the dumb cunt Anita was recently bitching about. Anita follows the SJW mindset, she blames the BBC, appeals to them to change it and make a Dr. Who that is trans because there aren't enough trans in sci-fi. An activist would fund and promote projects that has trans characters in sci-fi. There is no appeal to authority, it is basically creating what you want. For example, they could get enough money together to hire a screenwriter to make a spec script for a TV show or movie. OR they can support a trans filmaker through promotion and funding. Point is, they don't sit on their ass and cry and yell at someone else to do it.
SJWs have no capacity to create. They only bitch, whine and moan. You see this a lot. Same with PoCs in movies. SJWs bitch to the studios, activists fund, promote and engage in productions with PoCs already in them. Activists try to fix the problem themselves, SJWs try to make someone to fix it for them.
The reason why we see so many more SJWs than activists is that being an activist is a lot of work. An SJW can twitter bomb a movie studio or send out poorly worded emails and badly written blog posts rather easily. They want someone else to do the work for them. Which is why they'll never get the change they want because they aren't doing it themselves. SJWs are also actively harmful to the causes they promote, because they create a lot of friction between everyone and everything.
Activists are generally only annoying to people in authority, because they genuinely challenge the status quo. They don't demand more PoC in game of thrones, they find a way to make their own. And if its better, it challenges HBO. SJWs just make a mess for everyone involved, fans and creators.
In conclusion, SJWs are spoiled, spiteful little shits who are basically children throwing temper tantrums trying to get mommy and daddy to give them what they want. Activists go out and get what they want like adults.