While not the entirety of the under-representation situation, the pipeline is absolutely the biggest contributing factor. Take a look at any CS class today and you'll see a sea of white and east/south asian faces, an almost no black students – I took several CS courses at the University of Washington a couple years back (staff perk) and out of ~500 students perhaps 2-3 were black.
No amount of corporate diversity training or preferential hiring is going to fix that ratio.
No amount of corporate diversity training or preferential hiring is going to fix that ratio.