A big part of the world still does not have access to internet and consequently to social media. If social networks do promote new ideas, these ideas are restricted to a priviledged part of the world.
E. Duchesne discovered penicillin 31 years earlier than Fleming. He wrote up his findings in a thesis, but because he was unknown & young (only 23 at the time) the French Institut Pasteur didn't acknowledge his work. In those 3 decades, untold millions died of diseases that could have been cured.
The existence of social networks has made possible for knowledge to be democratic, since now is possible for everyone to produce, consume and share knowledge.
Just because you have nothing to hide, doesn't mean that people should violate your right to privacy. We should also consider the fact that in that we are running into new threats such as cyber warfare. Our information could be used by hackers, which they can use for blackmail or to expose our bank
Take the famous tedtalk called "The art of asking" about a women who is going through life mainly because of the way she uses the social media. In this ted talk she talks about how anybody from anywhere can ask for whatever they want and start any kind of initiative by simply making posting a tweet.
Most of the social media platforms have good and bad aspects to be pointed out. Information is completely available on the internet and companies in charge of social medias should take care of this as well. It is a case of using common sense and moral, on what is right and wrong and.
It might be irrelevant to apply the moral values and social laws that we have in our everyday lives, that is why if breaking the privacy is considered as a bad thing it doesn't mean that it's a bad thing online as well
We also need to realize that if it wasn't for massive social networks we would have not been able to connect with many people and could lose many great opportunities. For example many of us here in UWC found out about UWC through social networks.