Errors in Google's Rich Results Examples and Documentation

1. The example given for  Subscription and paywalled content says "1 valid item with warnings detected" when tested on Google's own Testing Tool.

When the @type is changed from "NewsArticle" to "WebPage", which is one of the Supported types, the Testing Tool says "No rich results detected". 

2. The example given for Fact Check, when tested similarly, says "2 valid items detected: All have warnings".

The warning is Missing Field (firstAppearance).

Update (~May 2022)

The documentation for appearance and firstAppearance under Fact Check says URL or CreativeWork.

Fact Checks with URLs for appearance and firstAppearance, that have been showing as valid on the Testing Tool for months, are now showing Structured Data Warnings on Search Console.

They continue to show as valid on the Testing Tool.

Update (Jun 2022)

Fact Checks with URLs for appearance and firstAppearance, which used to show no errors on the Testing Tool, are now giving Structured Data Warnings on both the Testing Tool and the Search Console.

The documentation for appearance and firstAppearance under Fact Check continues to say URL or CreativeWork.

Summary

The Structured Data documentation, the code examples, the Testing Tool and the Search Console are all out of sync in many instances.