If Oklahoma had the population density of the Netherlands it would have an additional 72 million people living in it...and oh by the way it’s got huge oil and gas reserves and some pretty enormous inland ports...
The Netherlands is, too, in the long run. But for now it's economically sustainable.
None of the other developed countries have vast interior deserts. The east and west coasts and some parts of the Mississippi and Great Lakes watersheds are plenty overpopulated.
I wouldn’t want to live there, but seems like a lot of bulk commodities, and products come in and out of Oklahoma and there is still plenty of room...
There are a few interesting studies in this area, California's agricultural section's tug-of-war with its residents for water is the biggest one that comes to mind, and the lesson you get is that industry uses up the lion's share of the water out of greed and sloth, but enough pressure will force them to curtail usage.