I've made plenty of left leaning comments that got flagged. Try arguing against the literal truth of the Bible or the necessity of religion to morality or society, for instance. Or that vaccines work. Or that free market capitalism has flaws and socialism has merits. Or that transgender identity is valid. Or that DEI is valid. Or that feminism is valid. Or that immigration and multiculturalism are valid. Or that gun control is valid.

There are tons of left leaning views that get flagged on HN. What matters isn't political polarity but the specific zeitgeist of the thread and whether you go with it or against it, and who happens to show up first with the most downvotes.