In other words, the music was no longer getting better, but it was going everywhere. Mass production and new technology are in the process of making electronic keyboards still easier to learn and cheaper than electric guitars. There is an ever wider variety of available sounds. With sampling devices there is no need to write a nice melody. Just drop in and splice the already existing ones you like.
Drum machines replace drummers.
Techies and nerds replace musicians and composers. As the price of recording hardware comes down, its size gets smaller, quality improves, and it becomes easier to use. Composers may not be getting better than Mozart, Gershwin or Wayne Shorter, but there sure are a lot more of them. And they are all over the place. People who have the opportunity to learn and can afford to buy the technology are able to make professional-quality recordings at home and distribute them over the Internet.