I think Microsoft is trying to fill in a meaningful, yet tentative part of the pie. It wouldn't be right for them to put forward the full cost of every cloud c

I think Microsoft is trying to fill in a meaningful, yet tentative part of the pie. It wouldn't be right for them to put forward the full cost of every cloud company's potential losses. At the same time it raises the stakes by begging the question for other cloud providers to fill in by asking "why isn't this higher?" So in that light, the number they've chosen may have served its purpose quite well, by encouraging others to think about what another massive 0-day CPU security flaw might cost them.