As I said, the video focused on Helvetica, which has been around for about 52 years now. Helvetica is a Sans Serif typeface that is used for headlines, signs and areas where large blocks of type are necessary. The video showed SO many examples where Helvetica is used. It it literally everywhere! I don't think you could get through a day without seeing it at least once. But why is this particular font so popular? Well, they asked many different graphic designers who gave their opinion on Helvetica and why it was so popular whether they liked it personally or not.
Those who were in favor of the use of Helvetica were for several reasons. First and for most, it is very legible and somewhat simple so the reader can focus on what it literally spells out instead of what the typeface is "trying" to say. Some referred to it as being "neutral". Others mentioned how it was a very stable and concrete typeface because of the negative space around the letters. They said the negative space was more important than the type itself and in the case of Helvetica, all the negative space was shaped in such a way that it created stability which they thought was a good quality in a typeface.
Those who didn't like it had their reasons too. One designer said that he didn't like it because it was a default. Everyone uses it, and why would you want to be like everyone else? Another said that it represented the Vietnam War and now represents the war in Iraq. So how could you like something that represented something so horrible?
I think one of the biggest reasons there are so many contrasting opinions is because of the generational difference. There are still so many designers out there who have had experience with hand techniques as well as computer skills and now, newer designers are entering the field with primarily computer experience.