S3 isn't JSON

it's storing a [utf8-string => bytes] mapping with some very minimal metadata. But that can be whatever you want. JSON, CBOR, XML, actual document formats etc.

And it's default encoding for listing, management operations and similar is XML....

> but I feel like we missed an opportunity here for a standardized interface.

except S3 _is_ the de-facto standard interface which most object storage system speaks

but I agree it's kinda a pain

and commonly done partial (both feature wise and partial wrong). E.g. S3 store utf8 strings, not utf8 file paths (like e.g. minio does), that being wrong seems fine but can lead to a lot of problems (not just being incompatible for some applications but also having unexpected perf. characteristics for others) making it only partial S3 compatible. Similar some implementations random features like bulk delete or support `If-Match`/`If-Non-Match` headers can also make them S3 incompatible for some use cases.

So yeah, a new external standard which makes it clear what you should expect to be supported to be standard compatible would be nice.