And I couldn't read the article without logging in to my Facebook account.
Facebook seems to put different restrictions depending on where you live. I'm based in Western Europe and never been able to read anything from Facebook without logging in. Same for Instagram.
I think Facebook makes a guess about whether you have a Facebook account or not (or, whether you are likely to log into it) and throws up the wall accordingly. If you'll just bail, they'll show it to you anyways. If they think they can force you to log in, they will.
Facebook seems to put different restrictions depending on where you live. I'm based in Western Europe and never been able to read anything from Facebook without logging in. Same for Instagram.