The impact of allowing high school players to be drafted is entireLy overrated and will likely only be felt at a few schools, Duke being one. Kentucky and UNC being others.
College basketball and the NBA survived when this was the case before and will again. While there may be a year or two of sorting out, when every 5 star HS player thinks he can be a pro, right now, the reality is that probably less than 5, more likely 2-3 will wind up on an NBA team in the year following high school. Also, probably 90-95%, or more, of the players in the G League will be better than the next level of high school players in any given year. In total, maybe 20 players a year will go directly to the “pros”. A huge % will still benefit, physically and emotionally, from at least another year of development at the college level.
The only thing that will change this is if the G league adds a second tier, which is unlikely to happen. Why would the NBA fund another level of minor leagues when colleges already provide this?
The only reason Coach K is complaining is because he will need to change his recruiting strategy again. Once you go the one and done route, you are locked in to it. You start getting huge holes in your class distribution from which it takes several years to recover. That is why he wants a transition or delay. Not for the players but for himself.