Why are books like this listed for the Booker Prize? What am I missing?

I read John Banville's 2021 mystery novel "Snow," and think about if I do or don't like mystery novels. 

Writers such as Yaa Gyasi, Teju Cole, Hishaam Matar and others are transforming immigrant writing by returning home. 

Some novels I've read come close to being perfect. Two examples are "Disgrace" by J.M. Coetzee and "Pale View of Hills" by Kazuo Ishiguro. I argue why.