I’m not sure there is a clear answer, however my gut says that Facebook is more net negative than iPhone. I wonder how much of that could have been avoided if more consideration was given while building out the Facebook, as was given when Apple built iPhone.
This is an interesting link and comment by @ben and I wanted to continue that thought by suggesting the opposite of Facebook’s approach. Move slow and Mend things. Take your time, consider the impact of your actions and the unintended negative side effects.
I wonder what this would also look like in my personal life. If I didn’t jump on the latest hype train but waited to let other -suckers- people test them out first and find the issues. If I were more critical of what I let impact my life than I currently am?