Would it really be hurting attendance though, since Disney is jacking up prices to try to keep people away from DL and WDW? Just look at the price increase of the DL AP in the past few years.
In 2016 the population of Texas was 27.86 million, as oppose to Florida's 20.61 and California's 39.25 million (just for comparisons sake).
The population of Houston was 2.303 million, Dallas 1.318 million, San Antonio 1.493 million and Austin 947,000. These cities are all within roughly 3 hours drive of each other. I don't think Disney would have any problem staffing a park in this area.
In comparison, Anaheim had 351,000 and LA had 3.976 and San Diego 1.4.
I really think a Texas Disney could be like DL, pulling a lot of attendance from locals.