I agree that this is a possibility and a risk, but I think that a bit of common sense goes a long way. One of my classmates tried to frame everyone who disagree

I agree that this is a possibility and a risk, but I think that a bit of common sense goes a long way. One of my classmates tried to frame everyone who disagreeed with him as nazi, but nobody fell for it, because it was obvious that he just tried to evade criticism. There also needs to be some leeway - for example a German court has ruled that a public service worker could not be fired for calling his boss an "old asshole", because they've known each other for very long. Context matters.