In the past, key exchange was hard. Now it could be as simple as walking to your local Bank branch and scanning a QR code on a plaque with your smartphone (as mentioned in the article).
Online-only or remote businesses like social networks and airlines would face a tougher problem.
Well, in the QR code and smartphone scenario, you also have to trust that the code in the smartphone all the way down to the hardware is trustworthy. Otherwise, you'll get attacked through the firmware or bugs in the OS or through custom sleeper electronics injected at the fab.
Online-only or remote businesses like social networks and airlines would face a tougher problem.