At first glance (by the name) I thought this was something that analyzed your AWS usage based on API logs and created an "ideal" policy for to use (or recommend permissions to remove/add).
You also have the problem that not all actions are recorded by CloudTrail (ex. cloudwatch:putmetricdata).
Now, I think that it's possible this tool could be extended to support that. For example... you could use Amazon Athena to query CloudTrail logs from an S3 bucket, and then query the logs to determine which principals touch which ARNs. For each IAM principal, create a list of ARNs. For each ARN, plug that ARN into a policy_sentry yml file, and determine the CRUD level based on a lazy comparison of the action listed in the cloudtrail log vs the reosurce ARN. And then run the policy_sentry yml file to generate an IAM policy that would have worked. But that's just my idea... actual implementation of that would be a bigger effort than what I could take on myself.
If you are interested in that kind of feature, please comment and I'll point this out to some other engineers who will be contributing to this tool as well.
Integration with cloudtrail sort of lands on teams, they suddenly get told it's a priority for that quarter, they scramble around like mad, shove a fresh-out-of-college hire on it with little oversight, and you get what you get...