1. If you switch the default SDK you still need to understand S3 to some extent. At least creating buckets, bucket policies, IAM, CORS headers and a few more. The complexity of S3 comes from it's architecture, not the SDK. In fact I believe the v3 SDK of AWS does a good job at what it is.

2. Feature extensibility. This way FILE0 is not restricted by S3 API limitations. One example being: the AWS SDK doesn't support advanced filters for files (like ends with .png). This is a feature FILE0 has, but not supported by the s3 api.

3. If the goal is to provide a smooth DX, you cannot start with "Go to your aws account and create a bucket, and add this configuration to your bucket".

A package like this would be interesting but it's not what FILE0 aims to achieve.