If you define "benefit to humankind" narrowly, and don't view gaining pure knowledge about the workings of the universe as beneficial to humanity, then most physics Nobel Prizes over the last few decades fail the test.
Detecting gravitational radiation from the merger of two black holes was an incredible step forward for our understanding of the universe. It will not practically change your life in any way.
"conferred the greatest benefit to humankind"
So while those things are cool and groundbreaking, I'd say they have yet to cross the threshold into "greatest benefit to humankind"