This doesn’t even go into the meat of it. To ensure smooth migration, Apple basically simulated the migration across a bunch of its devices and collected diagnostic data. And in collecting diagnostic data, checked for issues/addressed them so when it was go time, the risk was near-0. Now that’s engineering.
I am quite sure there were several examples regarding Apple software efforts during the time Steve Jobs was at NeXT, that wouldn't end up with "… now that’s engineering.".
Those would probably be "... now that's management edict"
Now That’s What I Call A Trainwreck Volumes 1-infinity