There is demonstrable proof that social media pressure is not enough to make amything outside of cosmetic changes and even in instances where you see social media pressure being exerted to shift policies, there are organized movements at the helm, taking to social media as an amplification of their efforts. Despite what content mills would have you believe, social awareness campaigns rarely if ever go viral. They are spread through organized hierarchies of "influencers" and coordinated efforts with hundreds if not thousands of users.
This is one of the greatest misunderstandings about content on the web, made worse by popular media narratives of the Arab Spring and other changes that were enabled by social media, but really were bolstered by groups that had long been in existence and were organizing with boots on the ground. Digital native social change efforts have been comparatively anemic.
I can give a lot of additional reading on this if you're interested as I was a communications director for a social cause up until a year ago when I switched jobs and have also devoted a great deal of academic study to this.
Here's an article by Malcolm Gladwell on it as some entry level stuff
Small Change - The New Yorker
But for a more in depth analysis, I highly recommend Evgeny Morozov's To Save Everything, Click Here or Astra Taylor's The People's Platform.