I doubt that being politically incorrect was the main reason that comment got downvoted.
For example, people might have believed for their own reasons that your comment was invalid. Or maybe they thought that since the topic often leads to dead ends, the comment should be downvoted as if you knew this and still headed into the dead end. People also may have interpreted you as trying to actually change peoples' minds, and thus felt disapproving or even insulted when you expected their minds to be changed by a small amount of evidence compared to that already available.
And what proportion of the downvotes came in after you added, essentially, "I'm so disappointed in you all for downvoting this." 50%?
People who go back and downvote every post or comment a Less Wrong user has ever made, please, stop doing that. It's a clever way to pull information cascades in your direction but it is clearly an abuse of the content filtering system. It's also highly dishonorable. If you truly must use such tactics then downvoting a few of your enemy's top level posts is much less evil; your enemy loses the karma and takes the hint without your severely biasing the public perception of Less Wrong's discourse.
(I just lost over 200 karma in a few minutes and that'll probably continue for awhile. This happens to me every few weeks. Edit: I mean it's been happening every few weeks for a few months for a total of only three or four. Between 400 and 700 karma lost total I think? I don't mean to overstate the problem.)