>thinking it was trying to improve and have a positive impact on the world
Were you like a very early employee or are you just that naive?
FB's intent became quite clear, quite fast in their history. Like, remember when they became so famous for their lack of ethics that even a hollywood movie came out whose plot is pretty much only about that?
And that was 12(!) years ago ... so, I am truly wondering, from where exactly did you get this idea of a company trying to change the world for good?