Should @id of parent objects be used as a base IRI for relative IRI references?

[trwnh]

By my understanding, the way to absolutize a relative IRI reference in JSON-LD is currently something like this:

• if the JsonLdProcessor has JsonLdOptions.base set, then use that.
• otherwise, if the active context includes a @base declaration, then use that.
• otherwise, if the document was fetched from a remote location, then the base IRI can be inferred by the IRI of the request.
  • if the response was HTML, then maybe <base> can be used?
• otherwise, emit a warning?

However, there is a possibility for objects to be nested or embedded in other objects. Especially in non-flattened form.

I would interpret a document like so:

{
  "@context": [
    "https://www.w3.org/ns/did/v1",
    "https://w3id.org/security/multikey/v1",
    "https://w3id.org/security/suites/secp256k1-2019/v1"
  ],
  "alsoKnownAs": [
    "at://atproto.com"
  ],
  "id": "did:plc:ewvi7nxzyoun6zhxrhs64oiz",
  "service": [
    {
      "id": "#atproto_pds",  // this is a relative reference, right?
      "serviceEndpoint": "https://enoki.us-east.host.bsky.network",
      "type": "AtprotoPersonalDataServer"
    }
  ],
  "verificationMethod": [
    {
      "controller": "did:plc:ewvi7nxzyoun6zhxrhs64oiz",
      "id": "did:plc:ewvi7nxzyoun6zhxrhs64oiz#atproto",
      "publicKeyMultibase": "zQ3shunBKsXixLxKtC5qeSG9E4J5RkGN57im31pcTzbNQnm5w",
      "type": "Multikey"
    }
  ]
}

where it seems like the node with "id": "#atproto_pds" is part of its parent context, the node with "id": "did:plc:ewvi7nxzyoun6zhxrhs64oiz"... which I think represents the document?

So the question is: Should the @id of parent objects be considered in the expansion of relative IRI references? If not, why not? If yes, should we consider only the top-level parent or should we instead consider the most recent absolutized parent?