[bdcravens]

S3 is one of the original AWS services (SQS predates it), and has been around for 18 years.

The idea of a propriety API becoming the industry defacto standard isn't uncommon. The same thing happened with Microsoft's XMLHttpRequest.

[crubier]

Also, the S3 API is simple and makes sense, no need to reinvent something different just for the pleasure of it

[ovaistariq]

There are valid reasons for extending and redoing some parts of the API. I will give you one example. Suppose you want to extend list objects to support ordering by last modified or you want to support filtering of objects by user metadata. Right now doing this is quite clunky via headers.