I don't think 4 Texas teams "became" regulars under Childress' watch but I think maybe I can work off of Rocco and make a point here...
When Rob Childress took over, the goal for anyone in this state was to overtake Rice and UT-Austin as the premier programs.
Their spots at the top were taken.
But not by A&M.
TCU is the premier program.
And Texas Tech's new coach, FWIW, has taken them to 2 CWS in his 4 years as head coach.
Regionally, the new Oklahoma State coach has done a good job. A CWS and Super Regional in 4 years. Van Horn at Arkansas has taken them to 4 CWS under his watch.
Nationally, the power has shfited, too. And A&M certainly hasn't been at the forefront of that power shift. That's been Virginia, North Carolina, Louisville, Oregon State, etc.