Best Practices - Doesn't follow JSON:API despite being a superset?
The Best Practices doc claims to be a superset of JSON:API, but the example data structures for resources and errors don't match the JSON:API spec (https://jsonapi.org/format/#document-resource-objects and https://jsonapi.org/format/#error-objects). The Content-Type isn't application/vnd.api+json either (https://jsonapi.org/format/#content-negotiation).
Should the document be rewritten to match the JSON:API spec, or should the JSON:API mention be removed?