The time wasn't really wasted on the marginal improvements, it was literally just wasted doing nothing, for example an entire 2017 roadmap of which nothing whatsoever was delivered, allegedly pursuing some "secret project" called Destiny which was apparently completely abandoned (if it actually existed in any meaningful way) with the 70% layoff. The actual improvements which have been deployed (few though they are) took relatively little or even in some cases very little time.