I don't know about that, he's obviously not talking about 94-96 Nas, it's 98-2000 Nas "the prophet".
He's obviously saying 'watchu tryna kick knowledge' as in the conscious shyt Nas was spitting was not knowledge.
Like asking a Mexican who speaks bad english if he's speaking english, when you know he's trying to speak english.
Or in Jay's own words
Cause the nikka wear a coofie, it don't mean that he bright
Cause you don't understand him, it don't mean that he nice
It just means you don't understand all the bullshyt that he write
Naw...its just a stupid line. Jay gave props to illmatic, right? Welp to that point that was Nas at his most conscious and thoughtful, so what Jay even talking about? Jay was just trying to appeal to the negative sensibility of black people that being smart is nerdy or weird. The ironic thing is that "trying to kick knowledge" was what Nas was moving away from, and his fans were pissed. The better angle for Jay to take, and one he flirted with but didnt commit to, was the fact that Nas had abandoned his deeper lyrical focus and was trying to keep up with the crowd by refashioning himself as a playboy/mafioso MC to awful results. Nas was completely playing himself, and after the beef he went back to his original style that made him world famous thanks to Mr. "Che Guevera with Bling on"