Not sure what is controversial about the Great Oxygenation Event. Some submissions are auto-flagged for any reason like having astroturfing history, some people

Not sure what is controversial about the Great Oxygenation Event. Some submissions are auto-flagged for any reason like having astroturfing history, some people don't like the source (I flag a lot of The Register articles as it's a low quality tech tabloid prone to posting manipulative flamebait, in my opinion), some people think it's against the HN guidelines or not front-page-worthy for any reason.