Diallo's situation may actually persuade him to play as well. Diallo didn't get to adjust to the NCAA pace of play and redshirted the second semester of 2016/2017, but redshirting didn't save him from being exposed. He didn't enter the draft when scouts said he wasn't ready, came back and struggled a bit as a redshirt freshman, only to get drafted in the back end of the draft when he had the talent of a first rounder (and has shown that so far this NBA season).
I'm interested to see what he chooses to do. You don't want to lose a year of eligibility, but I don't think he has any intention of staying in college for 4 years.