This is one of the major differences/problems with hip-hop as compared to other genres of music- the lack of knowledge of the history of the art amongst the artists. Its one thing for people on this board who are not emcees to be ignorant of certain artists, but for someone like Lupe who is arguably in the same sub-genre of hip hop that Tribe pioneered to take this kind of stance is questionable.
I was always a fan of Tribe, De La, Jungle Brothers etc. and am surprised that dude never heard Marauders, especially because "Award Tour" and "Electric Relaxation" where in heavy rotation on MTV raps. But his taste are his own and I can't fault him for not listening to Tribe, many people I grew up with didn't listen to Tribe. However, it is ironic that he mentions popularity and impact as his justifications for not listening to the album.
I know he feels he is being attacked and thus is being defensive, but he stands to be put in the same position 7-10 years from now. I can name 30-40 other emcees right now that are more popular than Lupe and Im sure that the next wave of non-threatening "backpack" rappers will say the same thing that he said about Tribe about him. If Lupe ever is in a position to be honored at a comparable event, which at this point is unlikely, it will be hilarious when some young upstart doesn't know the words to "Kick-Push".
This is one of the reasons hip-hop artists don't have the longevity of rock artists. You don't see Tool not giving credit to King Crimson (even brought Crimson on tour with them) or Metallica saying they never listened to Black Sabbath. Ozzy Osbourne is over 60 and he is still making albums and is making significant money from touring. Megadeth, Metallica, and Slayer have been around since the early 80's and still have huge fanbases and are respected in the current metal scene. What hip-hop artist can anyone foresee being able to do that??? The sad thing is that one day Kanye, Lupe, Jeezy, Joc, 50 etc will all be in the same position as these artists that they claim are irrelevant.