One stop shop? Even with an assumed "unified system" there is absolutely no way that even an incompetent group of IT engineers would be able to construct a single unified network with a single doorway into it to make a "one stop shop experience." It would still be "breaking into a thousand homes", but at least the difference is -- given a unified set of controls -- that reconciliation of a breach could be automated.
So, a nice convenient one stop shop for hackers.
I'd rather a thief had to break into a thousand homes than one great big home.