Porn isn't the case here.  It was an ASMR channel, as mentioned in the article, where she used a paintbrush on a mic. Yes, private companies can do what they want. That's why no one should build their platforms or brands on them because, any day, they can decide they don't like your content. I don't disagree with the part about porn being bad, but the stuff I see them ban and not ban based on sexual content is so subjective. So many sexual suggestive thumbnails on YouTube right now for clickbait never banned. The main point is Nostr is better for someone building a platform because you don't lose your following overnight based on suits deciding who also take orders from governments, as COVID showed us. 
Have a good one as well 🤝