You must be new to hip hop because literally every rapper ever has bit a line or flow from someone.
This! Jay Z has been going at it for nearly 20 years, if not longer and this video is how you judge him? Of course he has taken lines from other rappers, it is what they do. And yes, they all do it. At least in a lot of his songs, he acknowledges who he is pulling it from. "got to thank the homie Nas for that though".
Please tell me which rappers you like and I can prob give you a few songs that they do it too.
Also, Google search Jay Z conspiracies. Literally hundreds of people trying to hate on him, it's what happens when you get to his point in life.