Without seeing the whole story it is hard to say. Blizz does tend to be a bit more hands off with Guilds and Communities where a person voluntarily spends time - and has the tools to remove themselves from the situation. There is also the issue of “mutual combat” so to speak where two people willingly engage in an argument that just gets ugly. One or both may get a silence for a while if reported, but that falls into a different category than ongoing harassment.
Ongoing Harassment is a big deal and something Blizz takes pretty seriously. It takes time to build a case though and the person being harassed has to use the tools in place to block the offender/s. Once the offender goes around those tools then Blizz can apply different penalties.
The CS forum serves as an Information Desk and has an article about how it works.
The Forum Support Agents there would be the ones to ask about policies - they can often answer any questions or explain things.