1. Is there evidence that they've actually incited hatred and violence? If so, then they've violated the law. If there's no such evidence, then what justification would you use now?

2. Where's the evidence that hatred and violence are spreading?

3. Where's your evidence that censoring is successful in "stemming the spread of hatred and violence"?

Except the videos of Watson aren't spreading hate or violence but he is just another person with an opinion. Because it's unpopular opinion and because he worked with Infowars in the past it's easy to make him into the "bad guy".