I've never even heard of her and none of their works sound remotely familiar nor have I heard of the film her award winning book was adapted from...
I'm not sure how accurate that statement is.
0: https://en.wikipedia.org/wiki/Toni_Morrison#Awards_and_nomin...
It looks like she's mostly known because 4 of her works were featured by Oprah's book club. I generally don't base my reading list off of the recommendation of day time talk show hosts that have an intended audience of middle-aged women, largely house wives/stay at home mothers.
It's okay that you don't know who someone is, but there's no need to denigrate an artist or question their bonafides because you don't know who they are.
Think about it this way—if you came up to a random person and said "Donald Knuth is one of the most revered computer scientists in human history" and they said "well why haven't I heard of them before", would that mean Donald Knuth is a nobody, or that this person just doesn't really have any interest or background in this person's field?
I almost exclusively read fiction. I do not read a lot of (any) period African-American literature given I read for pleasure and not for tales of historically accurate racism and child molestation (The Bluest Eye apparently) in fiction (which appears to be her thing based on the 5 wiki entries I opened for her works).
Guess you answered your own question, a hole in your reading preferences is a reflection of you, not society. For the record I read The Bluest Eye in college and it was pretty eye-opening.