That's a non sequitur- EFS is a way to mount filesystems via NFS. What EFS does internally is kind of irrelevant- Amazon could implement it with NVMe, or whatever technology that they build internally, and the client would see the performance.

What exactly are you talking about? None of these things are comparable.

S3 is object storage. Ceph is a networked POSIX file system. HDFS is in between. All of them can run on NVMe devices.