Kanye was prolific, he wasn't a genius. He came out when hip-hop crossed over and had good beats and lyrical concepts, his lyricism fit in with the declining importance of lyrics in mainstream hip-hop, and the college theme for three albums was cool. Iirc, The College Dropout was the only album Kanye did the majority of the production on his own. All his other albums share production credits on the beats.
After he got too many co-producers on his albums and tracks, talkin' 'bout he was the new Andy Warhol and the Medicis it was the beginning of the falloff. Ye who a visionary had a prolific run and he probably singlehandedly elevated hip-hop to the white mainstream better than anyone before him, but his assisted creativity keep him outta the genius discussion. Ye was in the background long enough to know how to get himself in position to blow up.
He had a good run, he not a genius.