Is it too far-fetched for Mick to still be actively naïve and uncultured?

Like he's never heard of Tom Cruise or Mel Gibson (ironically, a fellow Australian) and when he goes to the the Wendy's drive-through, he literally thinks that the he's speaking to Wendy herself.

It isn't like Mick Dundee hasn't been to America before this movie. In fact, at the start of the second movie, he's seen to be still in New York with Sue.

And like I said, I would figure that being around Sue would help Mick become more cultured, civilized, and more in-tune with American life. So why is he still written like some sheltered hick?

We see Mick and his family living in a nice house in Australia, and his son presumably goes to a nice school there. So it isn't like he hasn't gained any sort of "class" or "sophistication".