I really hoped Juventus would be able to have 2-3 good enough players for the first team every 5 years or so, as bare minimum. But this never happened, unlike teams like Ajax, Lyon, Barcelona, or (just to stick with Italian teams) even Atalanta and Roma.
The real last bunch of good players coming out the Primavera were composed of Claudio Marchisio, Sebastian Giovinco and Ciro Immobile (people tends to forget Immobile was a product of Juventus youngs teams). I'm a lil' bit reluctant to include Moise Kean in the same category.
Other than that...