Here's the Rio Grande Valley Vipers top players last year:
RJ Hunter
Danuel House
Troy Williams
Demetrius Jackson
Monte Morris
Cleanthony Early
Tyler Lydon.
All these guys were the best players on their college teams (obviously for smaller schools than Kentucky or Duke). They are also far past being college seniors, the average age, I'm eyeballing, to be 24.
Do we think that freshman like Gabriel, Washington, Leaf, F. Jackson, Jeter, Brunson, Thornton.. could play on that team in their first season, to the point that they get drafted? I don't. I think the G-league will, generally, eat a sub-10 player for breakfast.