Unfortunately, every year there are dozens of kids who make the leap to the next level, even when they have no business doing so. Look, Isiah is playing himself into the first round, and if a kid leaves when he's being told he has a great shot at being a first round pick, all the more props to him. Guaranteed money in that scenario. If you aren't a first round lock, better to stay in school and improve IMO. Delgado falls into that territory. That said, it wouldn't surprise me, and I've heard repeatedly from those associated with NY/NJ hoops that both kids may leave if they have good season, which they both clearly are.
The above is what made the Kris Dunn situation so surprising. He was a lock first round pick last year, and yet he returned to school. That rarely happens these days. He is obviously gone after this year, and if I were a Providence fan I'd be concerned about Bentil leaving as well. He is built to play the 4 in the current NBA.
Unless Delgado plans on playing in Europe or Latin America next year. He's going nowhere.