Highly unproductive to write off the entirety of Texas like this. Have you visited Brewster or Presidio County, where this is happening, or spoken with the people who live there?

Big Bend is treasured by Texans across the political spectrum. I know nobody who is happy about this, regardless of how they vote. Environmentalists, ranchers, locals in general, strongly oppose this action by the Federal gov't.

The destruction in Big Bend is at the direction of folks who have never set foot there. It is not necessary. Just staying alive in that environment is difficult enough to deter mass migration. The existing River Road provides enough access, and probably some good vantage points (I'm not a border security expert).