Democrats probably won't win it in 2024 unless Biden walks the election like Clinton in '96. I think there is a fairly good chance that the GOP wins the White House in 2024, which could mean that Texas is a tossup in 2028. If Biden or Harris win the White House in 2024 then the GOP probably hold Texas in 2028 with 2032 the most likely time that Texas is a genuine tossup. I would not rule out the GOP holding it in the next 3 or 4 elections though.
Couple of things to remember with Texas is that it is a fairly young state and it still has low voter turnout so things could change quite quickly. It is also growing at a fair pace, meaning there could be as many as 3 million more votes for president in 8 years time.
This part is crucial. Texas is booming which many of you guys don't seem to understand, at least in terms of what large, sustained growths mean for a state's political trajectory.