Siri "uh huh" is impolite and moronic.

The "uh huh" is not a greeting. It's a why did you stop in the middle of a sentence. And it's oh so easy to avoid ever hearing it. Simply do not leave a pause between "Hey, Siri...." and your question. "Hey, Siri, what time is it in Belize"?

Using the feature as Apple intended is not what I would consider a workaround. But, I say tomato, you say pah-tah-to.

You cannot change the response.