Aren't we tired of saying this by now? That's fine, everyone can express her own views on Facebook, unless one is a Kurd who would like to say something about Kemal Atatürk? Should the Kurds have to create their own Facebook? Who's next, Trump voters? Do we really want them to sink further into their filter bubble?
At some point a service offered to the public must actually serve the public. We don't allow bakeries to choose which weddings they will cater. If you'll bake a wedding cake for $200, then you have to get baking, even if the happy couple with $200 are two dudes or whatever.