Fundamental problems

-you're assuming a structured software/app development approach, which is not feasible in the world outside powerpoint

-PKI/HTTPS are not bad in and of themselves. Individual implementations are bad.

-Lack of user education: there's still a fundamental disparity between what users are prepared to learn in the "real world" and what they're prepared to learn about computer use. Maybe the message is presented wrongly, maybe the consequences were never serious enough, but mollycoddling the plebs by placing all blame squarely on an evolving medium like applied crypto is wrong.

-John