Questions about ID and required fields

Context: We are developing a library to read JSON:API Schema data from Drupal so that it can be used by a JavaScript library to understand the available entity types and bundles available. Specifically this is for farmOS.js - which will connect to a farmOS site, which may have any combination of modules installed that provide different bundles for different purposes. So we're using JSON:API Schema to make farmOS.js able to determine these things automatically. :-)

Questions:

1. Why isn't entity id described alongside type, attributes, and relationships? (see first example code below)
2. Why are drupal_internal__id, drupal_internal__revision_id, and revision_translation_affected includes under the required attributes? They should not be required to POST. (see second example snippet below)

Example 1 (no id):

{
  "$schema": "https://json-schema.org/draft/2019-09/hyper-schema",
  "$id": "http://localhost/api/log/activity/resource/schema",
  "title": "Activity log",
  "allOf": [
    {
      "type": "object",
      "properties": {
        "type": {
          "$ref": "#definitions/type"
        },
        "attributes": {
          "$ref": "#/definitions/attributes"
        },
        "relationships": {
          "$ref": "#/definitions/relationships"
        }
      }
    },
    {
      "$ref": "https://jsonapi.org/schema#/definitions/resource"
    }
  ]
}

Example 2 (required attributes):

{
  "required": [
    "drupal_internal__id",
    "drupal_internal__revision_id",
    "revision_translation_affected"
  ]
}