Let's be perfectly clear. United failed to have regular success outside of Sir Matt Busby and Sir Alex Ferguson both happen to be two of the very best managers in Football history. United as a club has never built long term success, in fact United as a club has chronically failed to even build moderate success without these two great managers, one of the reason is that United instead of doing what every other big club has done which is not rely on managers but rely on technical directors that would build the club and maintain its culture while the head coach simply coaches the team that he is given.
And we should stop with this nonsense about soulless entity, there is nothing soulfull about doing a frankly moronic thing like relying on a single person for the culture and success of a club or any entity. It's also an insult to all the people that work, have worked, play and have played for United. United has historically picked the most volatile option, the one that create the weakest foundation, the weakest club culture and wannabe Top Reds actually cheer for it.