This is believable if Beto manages to regain his 2018 magic, but otherwise I don't see it.
He won't.
a.) 2022 is to be much redder than 2018
b.) Abbott is much more popular than Cruz
c.) Back in 2018, O'Rourke was young and fresh-faced; now, he's got 2018 and that quixotic 2020 presidential bid under his belt
d.) Related to c.), O'Rourke is much more polarizing because of his presidential race; I'd point especially to the AR15 line he made (TX loves its guns; even Democrats there like them)
We shall see. You raise some good points.