I don't think most people misunderstood your post; I think a bigger factor was that the content wasn't seen as particularly novel or interesting. ('My joke alludes to something important!' can only do so much to make up for a rubbish joke.) To the extent they did misunderstand, you can probably do more to prevent such misunderstandings by modifying your own behavior than by telling them to modify theirs. And to the extent you can usefully modify their behavior, using 'stupid' and 'autistic' as terms of abuse isn't an effective way to do it.
Recalling first that life is a zero-sum game, it is immediately obvious that the quickest and easiest path to success is not to accomplish things yourself—that's a game for heroes and other suckers—but to tear down the accomplishments and reputations of others. Destruction is easy. The difficulty lies in constructing a situation so that that destruction is to your net benefit.
The problem with destruction is that it invites retaliation. Even when your talent for lies, slander, and other dirty work is superior to your opponent's, he will still manage to cause you difficulties. When there is a third, uninvolved party, all they need do is stay out of it until you and your opponent have beaten each other down, and they emerge the winner.
It is therefore crucial that you prepare the way for your destructive ascent by polarizing the field into two camps. There must be no third parties or positions. If there are three political parties, you must begin by crushing the weakest. If there are three or more possible opinions on a matter, you must introduce terminology that conflates them and makes it appear that there are only two. Uniting your opponents is not beneficial, but making them appear to be united is, as it allows your attacks to strike them all at once. The vicious arts can thrive only when the apparent choices are first narrowed down to two.
(The mirror tactic is to narrow down the number of choices to one, and present them as two. We shall cover that in Dark Arts 201.)