That's great, but those metrics aren't available to us so speculating on that has little value.
1. Facebook's job as a corporation is to make money
2. Making money for FB is largely based on MAU
3. Playing politics and censoring the chosen world leaders of large portions of their user base is a probable way to lose those users, and thus, money
The assumption that people leave assumes that there is a different place to go to, which for most people, there isn't because social networks are exactly that: networks. Unless you have a small isolated network that can move all at the same time, it is not likely that people will single themselves out.