The electric guitar was the dominant technological innovation in musical instruments from+/- 1935 to 1970. After that, keys and digital technologies replaced it. So, no huge surprise - sunrise, sunset.
The Slow Secret Death of the Guitar
A really fascinating piece on the current state of the guitar industry.
https://www.washingtonpost.com/graphics/2017/lifestyle/the-slow-secret-death-of-the-electric-guitar/...
https://www.washingtonpost.com/graphics/2017/lifestyle/the-slow-secret-death-of-the-electric-guitar/...