All he's really saying is that it is important for things to be easy for people to figure out how to do, and for that you need to be aware of what mental models they already have and design interfaces with the goal that the largest number of users can succeed in using the software. A better analogy might be that if you're trying to run a political campaign, you should probably be speaking the language the majority of voters speak, and caring whether they understand you.

The examples the article gives seem like good ones. The starting point is a video of people new to linux trying to use software and failing to figure it out, acknowledging that as a problem to be solved. The proposed solutions are basically to have wizard guis that can walk users through the most common tasks for disk management and network drives. Usability matters and none of that should be very controversial.