It turns out that this term has been around for more than 50 years. It's an example of metonymy, a figure of speech where something is called by something associated with it, like White House for the Presidency, Washington for the United States government, suits for administrators, and so on.
Presumably, during the heyday of the Wild West movies, Texas became associated with the film-depicted excitement, confusion, violence associated with the "Wild West"**
And yet, I've never had the sense that I crossed over a cultural divide when I went to Texas, sorry, guys.
Anyway, some Texans are annoyed. But I have a suggestion for dismayed Texans: play tit for tat. Use a ju-jitsu move to their own advantage. I'm talking about letting language work for them.
Metonymy can work two ways, y'know.
Why don't Texans use the expression "totally Norway" to describe something as being staid, dull, utter predictable? Who knows, this could catch on with the hipsters in Austin (That movie was totally Norway!), football game attendees in Plano (A 0-0 tie? How Norway), or gourmets in Dallas (Pedro's burritos were simply Norway, no flavor).
But I can understand Texans' being troubled. What other American states managed to be enshrined in the vocabulary of the Norwegian language? What do people there say about Louisiana or Tennessee? Have we made the big time with international recognition, like Texas, California, and New York? And is it possible that the residents of some states actively embrace stereotypes of themselves?
There's an alternative plan. Go with and embrace the crazy Texas image as a compliment. After all, whatever one can say about Texas, it was never said that it was dull like Nebraska. As a matter of fact, Texas has to be in the top five interesting states in the United States!
**Very much overdrawn, methinks. But, after all, mundane doings don't sell books or movie tickets.