What about gays, atheists and others who could possibly damage far more than their own reputation?
I live in a country where I have absolutely no problem admitting to anyone that I don't believe in any gods, but it seems that in America this can and often has ripped families apart. Should those people be excluded from any public discourse regarding their beliefs?
The price which has to be paid in this dystopian future of yours is far too high, especially when the "trolls" you are trying to vanquish could just as easily be moderated out of existence wherever they became a problem.
How many other parts of our lives should we be forced to expose in order to take part in a community? HIV status? Voting history? Race? Whatever you feel the limit should be, I feel that peoples real names, races and locations is far more than anyone should ever have to share.
On a more mundane note, what about losing a job at Apple e because a search for your name brought up a few very negative, but non-trollish, comments you made about the iPhone, or perhaps Apple as a company.
These examples are generalised and unlikely... But not outside the realm of possibility.