I saw that transition. Curly chords are a fashion item. They were "modern". After years of only straights, we start to see curly chords as a "great idea" and people thought they were very "smart". What we might call "cool" nowadays. When I was young and curly chords were not so common, I too thought they were cool. You will also notice that electric guitarists used to use them
despite the hassle. Most of them got smarter.