I hadn't seen that before, and it indeed does support S3, but does it also offer the clients the downloads directly from S3, or does it merely use it as its own storage backend (so basically work as a proxy when pulling)?
But it still means a downtime of your service is a downtime for anything which might need a docker container, whereas if it went to S3 (or cloudfront in front of S3) directly, you profit from the many nines that S3 offers without paying an arm and a leg for ECR (data in ECR costs five times as much as S3 standard tier).
