Plus, scouts are more focused on pure velocity. Did you watch Tom Glavine pitch? Or going back furth, Mike Cuellar? Those guys couldn't break a pane of glass, but they would make batters look like Special Olympians with location, movement, and off speed stuff. Most fun pitcher I remember watching was Charlie Hough, a knuckleballer who would get guys tied up in knots...or get clubbed like a baby seal if the knuckler wasn't working that day. These guys could pitch a ton of innings without getting tired, and go on for decades - see also, the Niekro brothers.
I wonder if a lot of potentially effective pitchers never get the shot because their fastball barely breaks 90