It's that he gets people wound up enough to do that that amuses him. He's probably had that said to him literally thousands of times on Twitter and it doesn't make him change his behaviour so clearly doesn't bother him or else he'd stop trying to wind everyone up. People are free to do what they want but hurling insults at a troll who thrives on it just seems a waste of time, personally.
You're missing the point; the joy isn't in 'getting' at him; I doubt he even reads the responses now, the fun is in the hilarious and creative responses that people come out with, and the sheer unceasing shared relentlessness of it.
We are a broken and divided nation, and a splintered world, with further dispiriting evidence of our mass estrangement and fractured, solipsistic alienation bombarding our minds every day. But at least we have one thing we all share: at least we know, and can be reminded regularly, that we as a human race all agree that Keyes is an irredeemable unglabrous fuckheaded gimp of the worst, most slimy, most despicable kind.
It's kind of beautiful in its way, and maybe healing...