That's the optimistic angle; the pessimistic is that Helvetica grew in popularity due to its being nearly the polar opposite of a just-prior-to-mid-century use of Fraktur by a certain european political party.

(Helvetia itself gained a fourth national language in 1938, due to comments made by someone who made his trains run on time; the dutch reformed their spelling in 1947 to distance their language from a neighbouring country in the same language family who they had had the involuntary pleasure of hosting, etc. etc.)

Maria Ivanova tells her class at the end of the day that they should find out what their ancestors did during the Great Patriotic War. The next morning, she calls on little Johnny. He says "My great-great-grandfather was electrician: his helmet had two lightning bolts..."

Edit: added involuntary, for clarity. Neemt u me niet kwalijk.