Is this true? I don't have access to the article, but the Boeing crashes and other general loss of control/CFIT must account for a large percentage. Only stats I could find with a quick search are from Airbus who say LOC is the leading cause over the past 20 years (I can see enough of the WSJ article to see it says "...from 2014", so a decade and not like for like).
Edit: Possibly the linked stats exclude deliberate acts - wikipedia expands on this [1] [2]
[0] https://accidentstats.airbus.com/accident-categories/
[1] https://en.wikipedia.org/wiki/Aviation_accidents_and_inciden...
[2] https://en.wikipedia.org/wiki/Aviation_accidents_and_inciden...