Edit: LinkedIn says he was an engineering manager, then took a series of roles culminating in a data startup that got him into Facebook in the current role.
You do not get to the position he has at Facebook by having either ethics or morals. Having seen this up close at Facebook HQ I can assure you that everyone at VP level or above there knows what they are doing, knows the long-term consequences, and simply does not care because the paycheck is far too large for simple ethics to enter into the discussion.
The main issue here is people have different ideas of what is ethical. Disagreements arise when countries and increasingly companies exert power of people given to them by those same people.
In my mind, the same problems existed before facebook and expecting facebook to solve them for everyone is rediculous. Even more rediculius is expecting everyone to accept facebook’s solutions.