Nigga, you ain't live it
You witnessed it from your folks' pad
You scribbled it in your notepad and created your life

from Jay-Z – Takeover Lyrics on Rap Genius

The Illmatic album was indeed very observational, painting a vivid picture of street life as a whole, rather than simply recounting Nas' own (alleged) exploits. Jay is implicitly contrasting Nas to his own stance as a rapper who talks about his own street experiences. The line was a response to the hook in Nas' song Project Windows where he talks about his life in the projects with his parents.

“Lookin' out of my project window
Oh, I feel uninspired
Lookin' out of my project window
Oh, it makes me feel, so tired”

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