Recent relevant article with some interesting points of view, including a quote from Walt Mossberg:
"In the last couple of years […] I’ve noticed a gradual degradation in the quality and reliability of Apple’s core apps, on both the mobile iOS operating system and its Mac OS X platform. It’s almost as if the tech giant has taken its eye off the ball when it comes to these core software products, while it pursues big new dreams, like smartwatches and cars."
https://9to5mac.com/2016/02/15/apple-app-bugs-opinion/amp/
"In the last couple of years […] I’ve noticed a gradual degradation in the quality and reliability of Apple’s core apps, on both the mobile iOS operating system and its Mac OS X platform. It’s almost as if the tech giant has taken its eye off the ball when it comes to these core software products, while it pursues big new dreams, like smartwatches and cars."
https://9to5mac.com/2016/02/15/apple-app-bugs-opinion/amp/