It is definitely true you can play quarterback without being 6-4 these days.
But if you are going to take either a 6-4 quarterback or 5-9 quarterback, I would go with the taller guy.
USC decided it wanted the shorter one (Bryce Young) over the taller one (DJ Uiagalelei). But I never got the sense there was any strategy behind USC’s evaluations of the two quarterbacks.
I always got the sense USC had to work harder for Uiagalelei and it was easier to take Young, who really wanted to go to USC.
Maybe Clay Helton and Co. were right. Here’s another reason to doubt them though: Dabo Swinney wanted the taller one. He seems to know a lot more than Helton.