You could argue S3 is a key-value store, however ActiveMQ is a message queue, and EFS is essentially NFS. I certainly don't agree that 'anything that does perm

You could argue S3 is a key-value store, however ActiveMQ is a message queue, and EFS is essentially NFS. I certainly don't agree that 'anything that does permanent storage is a DB'. Not many people would call their hard drive a 'database' I personally think that they all have a place and are very useful tools for certain situations, depending on the problem.