Happens all the time in the EU.

Can't even incite mass murder anymore with being put in prison; it's political correctness gone mad!

I mean, given that you haven't provided any examples, I'm just going to go ahead and assume that the word 'critiquing' is being used very, ah, loosely, here. You can, generally, critique all you want; it's when you step over into inciting violence that you get in trouble.

Or by "critiquing immigration" do we actually mean racist dogwhistles against people who are the wrong colour? I sure hope not, but whatever sources for your claim you give can probably clarify this.