I think the article is completely wrong about the Supreme Court.
The tweet was on my understanding the day after it came out that the US Supreme Court might hear an appeal reconsidering gay marriage, and all the pictures that accompanied the tweet were about homosexuality.
Duolingo is a US company. It wouldn't make any sense for them to reference the U.K. Supreme Court some time after the judgment and without referring to the U.K.
Sloppy journalism.
And the JK Rowling thing was bad but at least they are acting quickly to remove it rather than doubling down. So many other companies would double down 🤷♀️