That was not how we treated the 9's at Google. Those had been tested through natural experiments (disasters).
I was not at Google for the Clichy fire, but it wasn't the first datacenter fire Google experienced. I think your information about Google's data placement may be incorrect, or you may be mapping AWS concepts onto Google internal infrastructure in the wrong way.
Do you mean Google included "acts of God" when computing 9's? That's definitely not right.
11 9's of durability means mean time to data loss of 100 billion years. Nothing on earth is 11 9's durable in the face of natural (or man-made) disasters. The earth is only 4.5 billion years old.
Yeah, that's definitely true. Google sort of mapped an AWS concept onto its own cluster splits. However, there are enough regional-scale outages at all the major clouds that I don't personally place much stock in the idea of zones to begin with. The only way to get close to true 24/7 five-9's uptime with clouds is to be multi-region (and preferably multi-cloud).
I have experienced many outages that were contained to a specific availability zone in AWS, from power failures to flooding to cable cuts. You are correct that 5 9’s still requires multi-region though.
I think also Google as a whole has pretty good diversity. But Cloud customers demanded regions in big population centers and smaller countries where Google traditionally avoided due to cost reasons. This lead to less redundant sites that were often owned and/or operated by third parties. So in the US and Europe you can probably trust GCP zones quite literally. But other regions (I have heard lots of rumours in the APAC) they may not be quite as diverse as they appear.
I think most Googlers actually don't know the specifics (I certainly don't know), and if they could, they probably couldn't tell you. It's sort of common knowledge that some of them are like this, but not exactly which ones.
I was not at Google for the Clichy fire, but it wasn't the first datacenter fire Google experienced. I think your information about Google's data placement may be incorrect, or you may be mapping AWS concepts onto Google internal infrastructure in the wrong way.