Lots of things are problem for people. World of Warcraft also does a marvelous job of keeping people isolated and stuck in their lower self. That doesn't mean:
- the majority of its users can do use it responsibly without adverse effect on their lives and those around them
- it needs to be banned, or even subject to extensive regulation
- the act itself is the root cause of said destructive behavior. People who let WoW ruin their lives often had other severe issues to begin with.
Among other things that can be highly self-destructive (and destructive to those around them) in the wrong hands: sports cars, the gym, fast food (>25% of the USA is obese, after all), online gaming, poker, literature... I could go on.
Hell, ignoring the moral side of it for a moment, legislating morality just simply doesn't work. Disregarding the justifications of Prohibition, from a practical perspective it just made things worse: it created a major avenue of organized crime, and failed to stop the flow of alcohol anyways. If the people want to drink, or smoke pot, or play poker, or log onto WoW, or chow down on a burger, you can't stop it.