Why Design Won’t Save the World?

I always used to ask myself if Design is at service of poor people and if it is about to be human-centred, so why, day by day it is getting away from its real purpose, which part is important for Design, this 90%, or that 10%:

“The majority of the world’s designers focus all their efforts on developing products and services exclusively for the richest 10% of the world’s customers. Nothing less than a revolution in design is needed to reach the other 90%.”