So many of us spoke up throughout the many years of failure and bad decisions. Our ideas and warnings were ignored. Instead, these "leaders" chose to trust and hire other incompetent partners (some still employed in the company). Who's truly at fault? Well, obviously the leadership you mentioned because it was their job to make us successful with THEIR ideas or at least to listen to reason from us, and they did neither.
Your idea, that if many would have spoken up it could've had a different outcome, is very valid. Great leaders talk to their people, listen to their employees, listen to their customers and take action to the common sense warnings right in front of them. This did not happen at Staples; or at least not when it mattered.
"SG, RS and now Sycamore" are the ones who had and have final say... and look at where we are today.