Sorry, I'm not following you here. The sensational-indignant OP, just like anything equivalent of whatever political flavor, is obviously not in line with HN. That should be obvious both in theory (https://news.ycombinator.com/newsguidelines.html) and in practice (https://news.ycombinator.com/front). So it was correct for users to flag the submission. Indeed, if people hadn't been flagging such things for well over a decade, HN wouldn't still exist.

I mean, if you want to argue that the story is actually a substantive and intellectually interesting one, containing significant new information (https://hn.algolia.com/?dateRange=all&page=0&prefix=false&so...), and it's just the title that's sensational-indignant, that would be fine. But that bar is necessarily pretty high when it comes to garden-variety political pieces. If it weren't, then HN would just be a political site.

Edit: btw, adding comments definitely does not help a post stay on the front page - see https://news.ycombinator.com/item?id=34041016.

Sorry but I really think you're off base. It's true that politically minded users (or partisans of any strong cause) tend to flag stories from the side they don't like. But it's also true that many HN users flag stories that they think don't belong on HN, given the site guidelines.