Intel has been giving developers free libraries for many years which use code specifically optimized for Intel processors. It seems likely that any app that uses one of these libraries will break. Even if Apple's emulator or compiler can work around these optimizations, Intel might release new versions of the libraries that will not work on an ARM processor.
Also, even ordinary changes to MacOS tend to break music apps and plugins. I would expect a change to a new CPU architecture to cause havoc there.
Any app that uses assembly code optimizations that use unique Intel instructions seems likely to break as well. Maybe Apple has perfectly emulated all Intel CPU instructions, but that seems very complex and how often does new complex software work perfectly? Having to buy/upgrade apps to run on ARM may be necessary. And will drivers for USB and thunderbolt peripherals all just work on ARM?
Intel has been giving developers free libraries for many years which use code specifically optimized for Intel processors. It seems likely that any app that uses one of these libraries will break. Even if Apple's emulator or compiler can work around these optimizations, Intel might release new versions of the libraries that will not work on an ARM processor.
Also, even ordinary changes to MacOS tend to break music apps and plugins. I would expect a change to a new CPU architecture to cause havoc there.
Any app that uses assembly code optimizations that use unique Intel instructions seems likely to break as well. Maybe Apple has perfectly emulated all Intel CPU instructions, but that seems very complex and how often does new complex software work perfectly? Having to buy/upgrade apps to run on ARM may be necessary. And will drivers for USB and thunderbolt peripherals all just work on ARM?