Because being able to dual boot Windows or even Linux is a serious consideration for important segments of the market. Companies that buy computers for their em

Because being able to dual boot Windows or even Linux is a serious consideration for important segments of the market. Companies that buy computers for their employees are going to be more hesitant to blanket approve Macs for their employees if they can't easily be repurposed to support their Windows (or Linux) need. Getting all software developers on board to do another architecture transition is also a massive undertaking. Apple has lots of experience in this area. Steve Jobs was asked how long the PowerPC to Intel transition would take and he said 7 years. That's because current Macs still need to be supported and some key vendors like Microsoft and Adobe were extremely slow at transitioning their products. LLVM bitcode is not architecture agnostic. You still need different builds for ARM vs Intel.