The point of the article is that libertarians defend intolerance, at the private level.
Be as intolerant as you like. I don't mind. Kick people out of the Scouts, don't rent to them, don't hire them, don't sell to them. We defend your absolute right to do so.
You don't need government to practice intolerance. When personal intolerance is practiced through government force against people who haven't initiated force or fraud, the result isn't merely intolerance. It's oppression.
And Act Up should be forced to have homophobes as their den leaders.