You seem to be very confused about what one is not allowed to say, "due to social convention," to put it in your words.
"I am against further immigration from the Middle East" is the predominant message from commenters on this forum -- overwhelmingly.
No one is restricted, or dragged off to prison for expressing the view. In fact, they are celebrated,  evidenced by the majority of commenters "liking" the anti-immigration rants.
Only a minority say more immigration is beneficial. And they are unfailingly castigated.
The prevailing 'groupthink' is anti-immigration, anti-taxes, anti-elites.

Labels: moderation: safe