It is very much possible to express controversial, contrarian or even outright silly views without being downvoted. The rule of thumb is to be respectful and charitable to your opponents and, well, read the room. The more your view diverges from the local mainstream, the better, tighter and clearer your argument must be.
If you make a comment here, it had better be either true and necessary, true and kind, or kind and necessary.
Recognizing that nobody can be totally sure what is or isn’t true, if you want to say something that might not be true – anything controversial, speculative, or highly opinionated – then you had better make sure it is both kind and necessary. Kind, in that you don’t rush to insult people who disagree with you. Necessary in that it’s on topic, and not only contributes something to the discussion but contributes more to the discussion than it’s likely to take away through starting a fight.
Nobody can be kind all the time, but if you are going to be angry or sarcastic, what you say had better be both true and necessary. You had better be delivering a very well-deserved smackdown against someone who is uncontroversially and obviously wrong, in a way you can back up with universally agreed-upon statistics… And it had better be necessary, in that you are quashing a false opinion which is doing real damage and which is so persistent that you don’t think any more measured refutation would be effective.
Regarding this, I like to quote Scott’s rules for commenting on his sites: