You go to the main website and plug in the paywalled URL.
The person you are responding to is just saving others that step.
oh.. I see.. outline bypasses the paywall because it strips all of the code away. I thought someone had to have access to the page without paywall first.
I went back up top, clicked on the example button, and it yielded https://outline.com/6ps979 "The Fasinatng… Fascinating History of Autocorrect"
(From Wired in 2014, totally off-topic, but with a few amusing illustrations in case you need cheering up from the sadness here.)
Just press the "web" link under the title of the article. It takes you to a Google search page and you can follow the link from there. News sites have to provide a free version of their articles for indexing and you can follow it to read pretty much any paywalled article you like.