Except their window system rewrite actually slowed everything down. Every single os release has added bugs to the graphics layer. I've been maintaining a simple

Except their window system rewrite actually slowed everything down. Every single os release has added bugs to the graphics layer. I've been maintaining a simple little screensaver since Mac os beta (almost 20 years old now) and the last 3 or 4 releases there's always something that breaks it. Bug reports go unheeded.