...because they are a billion dollar tech startup, whose end product/widget is security. Why shouldn't it be here? ...Because it's not about Uber-for-X? Or chat? or food Delivery? ... But everything they do is every HN buzzword: ML/AI/BigData/ES/JSON/CLOUD.
They are extreme users of tech and ingesting/processing more data in real-time than most of us can fathom.