Garrett Gilbert latest example of value in alternative leagues for quarterback play

Garrett Gilbert has been impressive in the preseason and is on his way to secure a spot with the Cleveland Browns, showing the value of alternative leagues for quarterbacks. The Alliance of American Football turned out to be a financial shell game and it might have damaging effects on the next league's attempt in the form of the XFL or another future league.
There are other players that participated in the AAF that are on NFL teams including two others on the Browns, both of which played for the Orlando Apollos with Gilbert. Alternative or developmental leagues have been good for the quarterback position in the NFL throughout history.
The AFL had Joe Namath, Len Dawson and Jack Kemp. The USFL had Jim Kelly and Steve Young. NFL Europe had Kurt Warner and Jake Delhomme. All of these quarterbacks are in the Pro Football Hall of Fame, save for Kemp and Delhomme, who both played in championship games or the Super Bowl.
Experience and opportunity matter for the quarterback position. And some of these quarterbacks that get to play a ton of snaps in these games facing defenses and live reps benefit. Garrett Gilbert was arguably the best quarterback in the AAF and it's carried over to playing the best football of his career in training camp and the preseason. Gilbert has a chance to be the AAF's legacy despite how short lived it was. He's likely to be a backup quarterback in Cleveland, but there are undoubtedly a few teams that wish they could get another look at him.
The NFL Collective Bargaining Agreement has restricted teams and coaches in terms of how much they can practice and how much they can work with players. Some of that is smart in terms of player protection. There's also a real downside in terms of player development and reps, so the quarterback position is suffering as a result.
An alternative or developmental league is great for quarterbacks, so it would be great if there could be a way to get one to stick to enable more quarterbacks to get reps and potentially create another good avenue to provide capable passers. Less teams would enter seasons virtually helpless.
There would be more paths to secure a good quarterback, which would have less teams turning the idea of tanking to get a top rated collegiate passer. It's not easy to do, but a viable alternative, be it the XFL or something else, benefits the NFL as well as the sport as a whole.
