The Blueprint 3 is Jay Z adjusting to a post Graduation world of hip hop. It wasn’t just him though.
From like 2007-2011, all major labels were pushing their rap artists to go towards that crossover style.
You can see it in Tha Carter III, Thank Me Later, Lasers, Recovery… etc
Blueprint 3 is such a weird/funny album
Jay tries a lot of ugly things on this joint