Use EC2, EBS, S3, Route53 plus EKS, RDS, ElastiCache.
But anything else that isn't low-to-mid-level (looking at you Beanstalk), use something better.
Clerk, WorkOS, etc.
Since the pool identifiers are static, how do you actually fail over?
Oh, you need a custom domain that presumably routes if the primary dies.
It felt like Cognito was abandoned for a while.
No clue if Cognito actually was KTLO though.