Online social activism according to me can be very powerful, especially here in the Western world. I remember for instance what happened in “United Airlines a few days ago, things went viral on social media and it made a huge difference (United Airlines within 48 hours saw a 3% decrease financially). In other words, the awareness was well raised. In the West it can be very worthwhile and meaningful.
In other parts of the world though Online Activism has very small impact. How often have we seen online activism against the North Korean government for instance, or bad treatment of women in some parts of the world? Have things changed though? Not really. I grew up in a country ruled by a “dictatorship type of goverment, and believe me online social activism is of small impact. So discouraging sometimes.
Now in regard to conversations about social justice online, they can be very heated. Very rarely have I seen people admitting their mistakes online. It educates people and can be very helpful though, but the common reaction of people has been to argue and complain.