First of all, this is about “YouTube banning 'medically unsubstantiated' content.” as well as content that “would go against World Health Organization recommendations,” which (if those guidelines are followed) doesn’t mean banning of people or discourse, but rather disinformation. Secondly, the WHO tweeted that, but had actually already acknowledged human-to-human transmission multiple times[1][2] in the days before the tweet, so no, I wouldn’t support banning discussion around a tweet.

1. https://www.who.int/csr/don/05-january-2020-pneumonia-of-unk...

2. https://www.who.int/china/news/detail/09-01-2020-who-stateme...