Well 2 commands...
aws rds export-task create \
--source-arn <SnapshotArn> \
--s3-bucket-name <Bucket> \
--iam-role-arn <Role>
Then copy it down aws s3 cp \
<S3 Location> \
<Local Dir> --recursive
The biggest effort would be then running the Apache Parquet to CSV tool on it.