During the 1991 war, most of the news sources couldn't figure out what to call him at all -- and many of them were slinging arrows at each other while doing it wrong themselves :) There were any number of Muslim clery or linguists or college professors that could have pointed them in the right direction, but the only "specialists" the news channels hire are retired generals.

Bush the Elder MAY have meant it as an insult ('yeah, "the Destroyer" ha-ha'), but it seems more likely that a) no one looked up his name and told the president what to say, or b) Saddam is just easier to say -- which I have a hunch is why most of us use it.