I made it about ten lines into this before realizing that, against all odds, I wasn't reading a postmortem, I was reading marketing material designed to sell AWS.
> Many of the largest AWS services rely extensively on DNS to provide seamless scale, fault isolation and recovery, low latency, and locality...
I didn’t get 10 lines in before I realized that this wall of text couldn’t possibly contain the actual reason. Somewhere behind all of that is an engineer saying “We done borked up and deleted the dynamodb DNS records”