This view is rather child-like - not childish. Something a kid in a philosophy/arts major would wax lyrical about. Well intentioned but wide of the mark.
You could vapourize humanity leaving a few thousand groups of kids. Check back a few thousand years later and governments will be up and running. The distribution of burden for our highly social species essentially dictates that we function in groups - whether that be your family, clan, tribe, town, chiefdom, city, kingdom, empire or state.
In less pie in the sky language - governments tax its people in return for stability, safety and meter out punishment fairly. The fact that you are alive is proof of that, seeing as the neighbour whom you hate hasn't yet killed you nor you him (hopefully) because going to jail is not appealing to either of you, especially if you kill someone for some absurd reason as they looked at me funny, I dont like em
The land you own and all your possession are garuanteed by the state. No one can wake up tomorrow and claim you are on their grandfathers goat farm from 299 years ago - even if true.
They govern completely different things (policies made and shaped for completely diff functions)and if this FB leadership was in charge of a country it would fail immediately. Apples to oranges IMO
If you're willing to admit that there are gradations to the inherent unethicalness of government actions then it's at least conceivable to grade them on the same ethical scale as every other group.
You have fundamentally the same position as someone who claims "there is no ethical consumption under Capitalism." There may be some truth to that worldview, but people have to live in the world where both governments and capitalism are the status quo. Both sentiments are broad enough to critique a large fraction of human society, and thus can be pulled out as a 'reason' for targeting any particular aspect one may instinctively dislike without having to put in the mental effort to determine why.
Secondly, you say Facebook has governance only over people who have given their consent. Taking second order effects into account this is clearly not true. Facebook was named as one of the "determining" factors in the Rohingya genocide by UN Fact Finding Mission. Negative externalities exist, and in practice they can be quite common.
Not to make @noooooo point for him, but you're forgetting about the most determining factor in that, the actual government that was doing the genocide. Maybe he has a point about governments being unethical...