Another way of looking at it: We have Jobs' iPhone because of Jobs' arch nemesis pet project - Sculley's Newton saved ARM.

The underlying OS has been cross-platform since the mid-90s. 68k family, Intel, PowerPC, Intel again, ARM.

The UI classes (Foundation & AppKit) themselves have also been portable. They ran on Windows (OpenStep NT) as well as NeXT.

The kicker was moving from NeXT to OSX where Display Postscript was dropped. That was a problem as the graphics primitives had to have their code redone.

Edit: essentially, they’ve been in a position to choose whatever hardware they needed.

Sure, but would iPhone Mobile Intel® Celeron® have worked?

Probably given the same OS ran on a 68030. Maybe it was a 68040, it was a long time ago.

Sure there will have been changes and bloat over the years.

There were Intel phones at 1 point. Wouldn’t say the hardware was perfect but could have been made good enough to at least work. The software held it back.