Freedom of speech is as alive as it ever was, I would argue with the current President and efforts to silence the media, there is more of a focus on free speech now than anytime in the last few hundred years.
What's grown is the complete lack of understanding about what free speech is and the responsibility that comes with having the right to free speech.
We are also still working out how free speech and social media can co-exist, and there are understandably some growing pains there.
Free speech, in most of the Western world, means that you have the right to voice your opinion in public, as long as you're not inciting violence or infringing on the rights of others (this is purposely a rather vague idea).
Free speech does not mean that people have to provide you with a platform. Free speech does not mean you get to speak and not be challenged for your views. Free speech does not guarantee you protection from any backlash that comes from stating your opinion, only that the backlash will not be legal action (again, unless you are inciting violence or engaging in defamation, etc).
The Facebook page you posted on, legally, is considered private. The moderators who manage the page have every right to kick you off for not agreeing with their opinion. Everyone has the right to kick some out of their private space for not agreeing with them if they so choose.
That's not being a snowflake, that's standing up for what they believe in.
If you went on a breastfeeding support group page and started harping on about the benefits of formula and how breastmilk is poison, you would expect to be kicked off.
Whoever runs the group didn't like what you had to say. So they exercised their right to privacy and autonomy and freedom of opinion and kicked you out of their private space.
Free speech in action.