To be frank, I think the real risk is still just… war. A big enough war where one side goes “no holds barred” in the cyber sphere will be a rude wake-up call. And we can’t do non-proliferation the same way we do with nukes. Otherwise as you say, the small and medium size things just happen sporadically. In an (existential or fully escalated) wartime scenario between countries, you get all the systemic risks hammered at once.