I publish a daily updated AWS IAM dataset at https://github.com/tobilg/aws-iam-data as well as historized managed IAM policies at https://github.com/tobilg/aws-iam-managed-policies
There's also https://www.awsiamdata.com/ which analyzes the AWS IAM data and also contains a changelog. Maybe this helps some people.
You can also query the data from your browser: https://tobilg.com/chat-with-a-duck#heading-explore-aws-iam-...