Imagine if newspapers in the time of the American revolution rejected all articles and letters without real names? There would be no revolution as it was largely argued and coordinated through the press. Even the Federalist Papers was written pseudonymously. What Google is saying is nothing of import should happen on G+.
I don't see how your conclusion follows: lots of important things happen without anonymity. Most civils rights leaders demonstrated openly and without the veil of anonymity. I'm not saying anonymity is never important, I'm just saying it isn't necessary as a condition of importance.
And a site requiring real names for account can still be used to communicate ideas anonymously. Similar to how money laundering works in US banks (which must be tied to a real name! OMG! How will anyone ever be able to use cash!). So on G+ you can have thought laundering!
Anyway, I just don't get why everyone is so anti-Google. Providing a service that requires someone to use their real name doesn't hurt anonymity anymore than putting a hamburger on the menu hurts vegetarians.
