That outage was limited to Route 53 DNS record editing and not DNS lookups.

Do you have a link to an article about that? My google-fu is weak, and this sounds interesting - that should not happen to DNS - at all - and from the outside Route53 looks quite well managed. So what the heck did they do?

It was back in 2019.

https://twitter.com/AWSSupport/status/1186735657387003904

I forget the details. I do remember half of our internal tools not working at the time due to DNS issues, though. Good times.