Why is RDS not considered an Abstracted Service? AWS manages the underlying service components and operating system. S3 and RDS both appear to meet the definition of an Abstracted Service in my opinion.
Dont know what you mean by ‘abstracted’. But RDS and S3 are completely different kinds of services.
RDS is configured/setup based on user choices – HW storage/sizing etc etc, and runs in the VPC (and old EC2-classic) and is Private.
S3 is Public requires no configuration besides nominal ‘settings’.
The OS instance in RDS would qualify as an Abstracted Service, since you dont have access to it. But the service in itself is not Abstracted, since its the Database Service you have almost full access to. Therefor RDS is not considered a Abstracted service,
The nomenclature can be confusing because each of the services is "abstracted" to some degree, but…
EC2 is an "infrastructure" service because you control everything from the OS on up, using native tools and techniques for such management, just as if it were an on-premise server.
RDS is a "container" service because you don’t manage the OS, but you directly manage the application (in this case, a DBMS) using native application tools and techniques as you would on an on-premise server
DynamoDB is an "abstracted" service because you don’t directly manage either the OS or the underlying application, but interact with the service via API calls and configuration settings