Then it's a bullshit argument. Good players develop elsewhere, you cannot just use a blanket statement and pretend Paro, Giovinco, De Ceglie, Palladino etc. were good enough but the club failed to develop them.
You don't make a pie out of shit.
Reality is the club never emphasized youth development that much. We took younger players from other clubs and developed them alongside established champions we had, but we also never had generational talents in our youth teams that the club didn't give a proper chance to and they went elsewhere to develop.