#1 - You contradict yourself implicitly with this defense. If a quote needs more context to have impact, then it is a shitty quote, which is what the OP said plainly.
#2 - 'Juvenille' and 'simple' are synonymous in this context. Period. Jay-z lyrics are more often then not, ridiculously vapid of substance or depth. Musical kool-aid.
#3 - Jay-z is a man who made his money ruining the lives of thousands by selling drugs, and millions more by being a horrific influence. He is a man who has admittedly attempted murder on more than one occasion. He is a man who has used and debased women proudly. He is a man of many transgressions. And I could look past all of them if he did not glorify them so.
Yet he does - so shamelessly in fact that its revolting to witness. His wealth and the adoration of the mindless sheep who buy his "music" are the justification he uses to continue to do so.
He says he'll always rap about variations on the same themes: drug hustling, business boasts, luxury hopscotching from Gucci to Louis Vuitton to the new Dior suit he says is a perfect fit.
I'm sorry his money and "accomplishments" and his poor excuse for music do not make this a praiseworthy man.