https://www.cnet.com/news/youtubes-super-chat-hijacked-for-hate-speech/

The use of Super Chat for such comments marks another example of how racist remarks and other inflammatory content finds its way online despite efforts at policing it. Facebook, Twitter, Google's YouTube, and others are all struggling to keep their platforms free of hate speech, misinformation and divisive material.

The Super Chat issue has apparently existed for a while. The Journal points to a BuzzFeed News article from May that says prominent far-right and white nationalist figures had been taking advantage of the feature for months.