Although what you point out may be technically (and marketingly) correct, it's not a stretch to consider the current, cloud-computing AWS to have started until

Although what you point out may be technically (and marketingly) correct, it's not a stretch to consider the current, cloud-computing AWS to have started until the availability of S3 and/or EC2. More importantly, for these services to run roughshod, two years later, over the technical assumptions of something like AWIS also seems reasonable to expect. If AWIS isn't integrated under IAMs, that's pretty telling.