At one time, capable executives could reasonably expect to build and maintain a healthy career without having particularly strong expertise in technology. (Unless, of course, they wanted to be successful CTOs or CIOs!) Not anymore. The advent and explosive growth of the digital age has transformed the game, probably forever.
I was going to use the decline of the buggy whip industry as an illustration here, but online research showed me that this analogy is a bit off base. For example, one article indicated that companies that survived the emergence of the automotive industry most successfully were those able to adapt their technology for use with automobiles. Presumably, their executives saw a path that would position their companies for survival—and took it.