Yeah that's what I disagree with. And its not about board members only - rank and file employees regularly get fired for expressing opinions not endorsed by their orgs.
you still have free speech - what you don't have is immunity to real world consequences if your views are so far out of whack with social norms regarding exploitation of vulnerable groups (eg. underage kids) that your coworkers and colleagues do not wish you to be representative of their organisation or their leader.