With the number of changes that have happened with Apple's, Microsoft's and Google's various OSes over that period it's hard to say that GNU/Linux isn't being held to a higher standard here. CentOS being the trademark-stripped knockoff of a corporate OS is the reason for the instability - when you deal in corporate OSes, you're subject to the business strategies of their sponsors. Some would say (weasel words) that the strategies of the sponsor of CentOS have been the source of instability and conflict across Linuxen for a long time now.