In the video, he stresses pretty hard that all forms of cloaking are disallowed, even if not malicious or deceiving. Unless the Googlebot has a paid subscription to WSJ that's still cloaking, as you're showing Googlebot a different page than a regular user.

Google's rules and help documents are spread all over, but here's some from Google News about subscriptions:

"If you prefer this option, please display a snippet of your article that is at least 80 words long and includes either an excerpt or a summary of the specific article. Since we do not permit "cloaking" -- the practice of showing Googlebot a full version of your article while showing users the subscription or registration version -- we will only crawl and display your content based on the article snippets you provide."

edit, forgot link: https://support.google.com/news/publisher/answer/40543?hl=en

> sing-up page.

That's a new one. Buy a subscription to the WSJ now for a song.