"a beacon of all that was great and wonderful about social media"
The issue was most journos are "social" people and nosy ones :) And despite their job, many of them may not be the most successful one in their social groups - especially those following tech news.
Media organizations too like easy sources of personal data, especially gossip and a variety of silly ones. They saw it as a source of easy revenues.
The idea they could find a lot of people activities, feelings and thought - and lot of images - looked incredible to them. Look at how they raid social profiles of dead people... once it took a lot of effort to collect those data and publish them to attract morbid readers. I think they started to believe Santa Claus was real.
That coupled with strong PR efforts made FB the darling of most media. Only a few one understood how dangerous it was since the beginning - and that even without knowing before how Zuckerberg made it starting raiding female students photos to build on "men's" basic instincts... yet the honeymoon lasted too long.