Why would the NBA set a deadline that only helps the colleges? Why would the NBA set an obligation the kids have to meet for the college? How would they even enforce that?
If this is about the kids, let them go through the process, weigh their options, and then decide.
I do not know, maybe to work with the NCAA so that kids do not squander a chance to get some college education and / or a year under their belt for the ones that are not ready for the G-League even if the player thanks they are. Well hell just let kids that are sophomores and JR's go if THEY feel they are ready. NBA just wants talent. Which is NOT the case. The NBA just wants the true One and Done "can't miss" kids. I can guarantee you they do not want 30-40 high school kids a year jumping on board. they do not have time / resources to try and evaluate that many kids at one time. remember, there are only so many teams and roster spots, they will try and work to some capacity with the NCAA. They almost have to. if would benefit both to have a deadline and parameters for players that qualify for G-League.