Huh. I just tried it on this article and it failed for me as well. It worked recently but they must have closed off that loophole.

Now to see if Google penalizes them. Not holding my breath.

Why should they? There's a paywall, it's no secret.

Because Google wants to provide people with useful search results, and "you can't read this article unless you pay us" is considerably less useful.

If you have a paywall, Google will still crawl and index your site, but they'll only do so based on what's available outside the paywall.

If you try to trick Google by showing Googlebot the full article but throwing up a paywall for everybody else, Google will penalize you.

Details: https://support.google.com/news/publisher/answer/40543?hl=en

It seems to only work for mobile now; I could not get it working from a desktop browser (with or without incognito mode), but using the web AMP link from my mobile shows me the whole article.