Because KSA doesn't have a populace that you could rightly say wants democracy. They want radical Islamism. Many Iranians want democracy; it'd be spitting in their face to support the religious dictators they have been tortured and murdered by opposing. By supporting the Iranian leadership you are pretty much telling democrats in Iran to give up, because now they have the support of Russia and the US. Game over.
The criticism of his callous behavior in Cuba is NOT absurd. It's absurd to support it. Can you imagine if the PM of the UK was laughing and playing golf with Kim Jong-il on September 11th, after learning about what happened? Obama is a long-term guy. He believes that, in the long-term, things like a few dozen, or hundred, people dying is no big deal. Everything will work out eventually. Maybe "eventually" is 50 or 100 years, but we'll get there eventually. Why worry?
Typical ivory tower guy.