Whether it's a sense of superiority or just to be funny or asinine or out of a genuine need to spread the truth, people online generally try to be contrarian as often as possible because it gives them some sort of personal gratification or a sense that they're correcting something wrong in the universe.
Yes, but not necessarily in a bad way. I enjoy finding small issues which others may not typically notice; half the time they are taken as intended (see: https://lemmy.world/comment/9002659), in a collegial way. I don't intend to be contrarian per se, which I think is at odds with your mention of correcting something "wrong" as you can be contrarian just to annoy rather than because there's an issue.
It's nice to be able to think things some people refuse to think. And I do sometimes feel superior in being able to do that.
As a contrarian, also no.
My personal brand of contrarianism is trying to understand people. I feel like I get much further in understanding others from my perspective by opposing theirs. But I'm also willing to meet them half way if they participate.