You seem to miss one important point - Twitter is optional. Being bullied in the schoolyard is not a situation a person can easily remove themselves from. Robbie Farah can slap that logout button and never look at twitter again for the rest of his life with no impact on his life. Extend that to the entire internet. Carefully self-moderate which sites you visit and use and you will probably never see another hurtful thing posted online in your life.
If you don't like the way Twitter works don't use the f**king thing. Set up your own alternative with terms of use prohibiting any mean tweets and moderate it yourself. You CANNOT use the government as a tool to push your version of politeness or morality onto the rest of the population! Wake up to yourself. The UK is a police state, and it worries me that there is a significant portion of our society who is keen to push our country that way as well.
Edit: Sad that I have to post this, but I'm going to preempt the inevitable response and say I DO NOT AGREE WITH WHAT THIS PERSON POSTED ON TWITTER.
This is what you rightwing hyper free speech types don't understand. If you think he has a right to say those things, it's as good as agreeing with it.
You're either for it or against it.
Btw, it's not about pushing ones own version of morality on other people. This isn't about morals. This is about law and order. We don't allow anarchy in the streets so why should we allow it on the internet
As for your "just log out" suggestion. It shows ignorance about gen Y and younger society. If you "just log out" from social media it's like locking yourself out of a community of your peers. People use social media to network among their professional peers, for some it's used as the main way to study for and do schoolwork. For somepeople opening up social media in the morning is the equivalent of when their parents generation opened the morning paper.
There are people in there 20s now who have applied for and interviewed for every job they've ever had via social media.
Social media is becoming less and less a luxury and more and more an absolutely necessary part of daily life for young people.
And just like we have a right to walk down the street without being abused, we should have the right to be a part of social media without being abused.