If I remember my American History, Texas modified or rewrote its constitution to the satisfaction of Congress to regain its membership. With the “election” of Rutherford B. Hayes in 1876 (or 1877), it was all for naught as the GOP withdrew all the safeguards for Black Americans, setting us back for another century. Trust me, I’m not naive, we have a long way to go yet but the 13th, 14th and 15th Amendments were a good start.
Has Texas really changed after 150 years? Sure, namely in the urban areas which is a normal thing given the trend with all civilizations. It will be up to us in Houston, Dallas, San Antonio, Austin and El Paso along with other university pockets to bring the Lone Star State into the 21st Century. We won’t be another California, just not a giant Alabama or Mississippi.