That’s pretty fucked up. Having another opinion is not grounds for losing your residence permit.
What’s with that paltry gotcha question? You do know there have been plenty of other groups as bad as or worse than Da’ish and we’ve been dealing with their admirers ever since.
As a matter of fact, yes. Even returning ISIL fighters weren’t deported back to Syria. There are methods of dealing with disruptive individuals that don’t boil down to “getting rid of undesirables”.