That's not how the whole thing works and you need to understand the process. You seriously want college football coaches to read every email they get from fans, let alone respond to them?
They have an entire support staff to receive your email. And even then there's no obligation to respond.
Imagine having to say thanks to every parent or fan who thought their kid was the next big thing and they need to look. And how many of them are not close to being worth looking at.