If this game follows the majority of all MMOs you don't really have open mics to hear everybody you just use your own teamspeak server or vent server. If they do have a mic system included my guess is that it only works within guilds or parties and will again not be an open system.
Pretty much this.
This problem is really only relevant to arena-type shooters and other such multiplayer games with built-in voice comms. Not really an issue for MMOs.
That kind of language is hardly seen in MMO's 99% of the time guilds will have their own teamspeak or vent servers which they either run themselves or pay for per month. The admins have the right to ban anyone and all times I have seen when someone is as abusive as the person in the video they are silenced and can only listen if they persist in bad ways then they are banned all together from the VOIP server. And in extreme cases removed from the guild or clan.