That is a top 'did you know' factoid that I am sure I will tell others.

But do AT+T engineers carry T-Mobile phones?

If yes then they should put themselves together a deal so that none of the on-call engineers have to worry about running up big bills using their phones. When there are freak weather events they are all in it together.

And Amazon. I recall that during their most recent s3 outage Amazon's status page was green across the board, because somehow all the assets that were supposed to be displayed when things went wrong were themselves hosted on the thing that was down.

Some thought they were spreading eggs across multiple baskets by replicating across regions and trusting Azure was doing the same for their “global” services.

As a consumer, the lesson here is that Azure is one, big basket. It would probably be prudent to think of AWS and GCS as single baskets too.

[citation needed]