.....one benefit that has been omitted.....it enables a good student to graduate in 3 (with AP entry credit) or 4 years and start a graduate degree while remaining on scholarship. There was a kid at Penn State a few years back that was able to graduate in 3, do his graduate degree year 4 and started medical school in his 5th year. He even got a 6th medical waiver year. A rarity for sure, but it worked to his benefit. His was footballer, so he was on full scholarship for all 6 years.
Flip side, the Ivies limit eligibility to 4 years, no redshirts, no medical waiver years, though some of the schools promote a training year off before enrolling for your first year. The Ivies do allow an intern year out of school. UPenn used to push that one. Academics and sport for 2-3 years, then they would line you up for a year away interning, often at a Wall St brokerage where you would get paid a tidy sum before reenrolling to finish your eligibility. The NCAA accepts it since they are still competing in 4 of the allowable 5 years.