They are missing huge parts of this story, they do emphasize a few times about the age of the game, but don't mention how much time/effort/money it would take to patch that into the game. Not to mention the amount of players that are there it makes it hard to hire enough people to moderate all the channels in the games, so they rely upon people to report abusers, and when no one reports, no action is taken, no review of the account is made. It takes more than a singular report from a single person to trigger the system into forwarding it to either automated action or for further human review. Is it a good way for them to moderate the chat? Not really. Is it effective? I feel it can be, I know of a few people in World Of Warcraft that have received multi-day bans for abusive language, and they now try to keep it clean.. But in the end, it still relies upon you the player to not ignore it, and report the issues. If they don't know, they can't act, and have a sense of plausible deniability.
However, when coming into this video, I honestly expected some sort of expose on the SC2 community as a whole, not a "I saw bad things in one game, and here are a couple of complaints in another game, and why don't they do what they do in a brand new game in games that are 10+ years old." I am not saying that this is not a story, but the way it was presented almost makes it come across as a non-story. If you wanted toxicity in SC2, start looking at r/Starcraft, start talking to the casters, specifically Artosis, Nathanias, Rifkin, ZombieGrub, Feardragon, those guys have all faced one form of community toxicity or another over their careers.