Ryan Schultz has a good write-up of tools that social VR platforms are using to prevent or at least minimize trolling, a problem that's so pressing and pronounced, it's keeping many VR users from using social VR at all. I'm fascinated that High Fidelity and AltspaceVR have a "bubble" tool that enables one user to become invisible to others -- in other words, it doesn't remove the troll or punish the trolling behavior, just makes the user invisible to the troll. (Thereby ceding territory to the troll, too.)
Also noteworthy: Ryan's post was published last week, and includes this line: "We’ve been pretty lucky in Sansar so far; we haven’t seen anything like the levels of trolling and harassment that occur in the more popular social VR spaces like VRChat and AltspaceVR." But just this week, Linden Lab is reporting that its own staff is getting trolled and harassed in Sansar. Which is to say, the problem keeps getting worse.
There's really no perfect solution to troll prevention without any downsides. I'm inclined to support a Reddit-type system where trolls can be downvoted into a ghost-like state where they're no longer able to interact with others. (But I freely admit that that's got problems too.)