The "contrarian dynamic" (https://hn.algolia.com/?dateRange=all&page=0&prefix=true&que...) is the tendency for reflexively negative comments to show up early with shallow/generic objections to a submission, followed by a later wave of comments objecting to the objections and defending the submission.
The latter tend to get upvoted—rightly so, since they are more positive and usually more substantive. This puts the thread in the paradoxical-but-common state where the top comments are objecting to how prominent the bottom comments are! (Or, rather, were.) That's odd, but at least it's better than having the negative ones at the top.
In this case, these 5 comments all appear higher in the thread:
https://news.ycombinator.com/item?id=45528218
https://news.ycombinator.com/item?id=45527967
https://news.ycombinator.com/item?id=45527886
https://news.ycombinator.com/item?id=45527879
https://news.ycombinator.com/item?id=45527728
... than the negative(ish) ones that were posted earlier:
https://news.ycombinator.com/item?id=45527887
https://news.ycombinator.com/item?id=45527480
https://news.ycombinator.com/item?id=45527387
https://news.ycombinator.com/item?id=45527278
https://news.ycombinator.com/item?id=45527259
Some of those were only slightly negative and probably not meant that way, but yeah, the early impact of running into a bunch of these leads to a WTF feeling.
Ultimately I think this has to do with the reflexive/reflective distinction: https://hn.algolia.com/?dateRange=all&page=0&prefix=true&sor.... That's probably the clearest way of describing the difference between the kind of comments we want on this site vs. the kind we don't want.