Here is a picture in words:
“If you saw Atlas, the giant who holds the world on his shoulders, if you saw that he stood, blood running down his chest, his knees buckling, his arms trembling but still trying to hold the world aloft with the last of his strength, and the greater his effort the heavier the world bore down upon his shoulders - What would you tell him?"

Exactly, using my last example above.
Seeing in pictures AND using words rationally is an unbeatable combination.

However, the youngin's these days only use and respond to pictures...just go to facebook...that's 99% of what you see there.

When wannabe novelist me is writing a scene, I visualize it. Then I use words to describe it along with any dialog and action.

And that's the overall point I think...much of the world is not literate and the proliferation of Pictures in social media only perpetuates the thinking in pictures eliciting irrational emotional responses.
However, one can "Think" in pictures without the emotional responses, for instance, forming a plan of action or development of an invention could be formulated this way.

I do not know about "most" people; and I suspect that the author and his sources do not know "most" people. The anecdotal examples are interesting support for the thesis, but the actual quantity of "most" people believing this or that has not been established.

Moreover, I point out, that even if "most" people still think in pictures as "most" people did in the Stone Age, the fact remains that millions, perhaps a billion literate people are linear-rational thinkers. In addition, it is also true that linear-verbal reasoning is also limited by its nature. The best thinkers unite both. This applies not only to verbal exposition and debate, but to music, sculpture, and theater (cinema). It is the objective mode of thinking.