Well, yes, but that's why we do the whole voting thing again after a period of time, rather than just once. Democracy isn't a means to ensure bad decisions won't get made, it's a means to ensure they can be un-made.
"Many times, perhaps most times, the crowd votes after someone bold has already moved and shown the way. That's what Swartz was doing."
You missed the point of Kerr's argument, which was that what you describe isn't what Swartz was doing. You're describing a Rosa Parks strategy -- do the minimum necessary to break an unjust law in order to elicit punishment, and therefore draw attention to the law's unjustness. If that's your strategy, the prospect of going to jail isn't a defeat, it's a victory.
But Swartz, Kerr argues, wasn't following that strategy; he was doing something different. He did much more than the bare minimum necessary to elicit punishment, and his actions indicate that the prospect of going to jail represented an interruption of his plans, rather than the culmination of them.
Swartz was not acting in the grand tradition of civil disobedience in which one willingly draws punishment to bring attention to the unjustness of the law. In his own words, he didn’t want to “just send a strong message opposing the privatization of knowledge.” Rather, he wanted to change the facts on the ground to make his preferred world a fait accompli. That is, he wanted to make the laws unenforceable, winning the debate unilaterally outside of Congress.
In this line of thinking, Swartz isn't Rosa Parks; he's Al Capone, if you can think of Capone's flooding the streets of Chicago with bootleg booze as a protest against Prohibition. Effective? Sure; the cops can't bust everyone if there's a speakeasy on every corner, and if the law is being routinely flouted by millions every day its absurdity is obvious. But because it involves doing much more than the minimum required to violate the law, this is something qualitatively different from civil disobedience.