I'm not sure it's the sole cause, but it's true and other schools do the same. At most schools, if you have a recruit you really want but who can't make the grades, admit him to a low-effort major, whether that's Communications at Stanford; African, African-American, and Diaspora Studies at UNC; Family Studies at Florida, etc. GT doesn't have a low-effort major. Then private schools have an additional advantage because they do not have public oversight of their admissions processes, so they can further bend the admissions guidelines (waive required HS classes, waive SAT requirements, etc). Though the fact that 60% of UNC players have a 3rd grade or below reading level tells you public schools can do it, as well.
Frankly, GT could do this as well if it got creative. We could dual-admit with Kennesaw State / Southern Poly, which would allow football players to take KSU courses but play football for GT. Tech already does this but defers the Tech admission until completion of the REPP transfer courses. Just change that to dual admission for athletes in a non-engineering major. Take 2 years of general education at KSU, then 2 years of digital communications at Tech (Tech really needs to look at expanding majors, not just because of sports) and get 2 degrees. Meanwhile, play for Tech the entire time.
We just need a president who sees the marketing value of sports and makes it a priority.