> it will be seen by their families, friends, classmates, professors, coworkers, bosses, etc.
That's what visibility controls are for. You don't have to let everyone see what you post, and I have many friends who use that to post things critical of the Chinese government, mostly on topics like censorship or the relationship to Taiwan, especially when the referendum on gay marriage was in the news.
They trust post visibility controls to hide their posts from the government? Hell, I wouldn't even trust those to hide them from anyone, really. Too man bugs in software, too many bugs in UX, too many terrible business decisions ("we'll just remove these to expand user generated content and drive up enagegement levels"). When you give me "controls" I don't control, I treat them as if they are always set to the worst case possible.
The government knows anyway. Half of the posts about censorship I see are just screenshots of two sides of a conversation, showing which messages didn't make it to the other end. The visibility controls are there to hide that stuff from people who're not part of the government.
That's what visibility controls are for. You don't have to let everyone see what you post, and I have many friends who use that to post things critical of the Chinese government, mostly on topics like censorship or the relationship to Taiwan, especially when the referendum on gay marriage was in the news.