Im not certain I buy the arguement that the decline of mozilla is purely a bad management situation. In threads about this, or pocket or cliqz or any of the other mozilla diasaters of the last while, you have a huge amount of what appear to be line level engineer employees defending this crap voraciously.
Something has gone very wrong with the culture of mozilla in general, I think its a copout to suggest that its merely some evil pointy haired boss.