Microsoft is in a slightly better position, because most business software these days are .NET, and if it's compiled Machine Independent, then it runs natively on any CPU. They use software emulation for x86-32, but for some reason that doesn't work with x64. In the Windows world, most software are still 32-bit. I can't imagine it's efficient to emulate x86 from software. Z80 (ZX Spectrum) or Nintendo for sure, but x86 I don't think so. However, business applications aren't usually very demanding on the CPU in the first place. A business app with a dumb dialog box is easy to emulate from software. Try running Premier on x86-emulated ARM.
It is true that separate Intel and ARM MacBooks would require a lot of extra development and maintenance effort. I'm not sure they'd do it. It's more likely that they'll move a lot of services on ARM, while keeping the main system Intel. Encryption and video decoding have already been moved to ARM, but they could move more features there. Neural networks, JPEG compression, dozens of services could be moved to ARM. But that misses the whole point, because as long as the OS is running on Intel, you're not saving much power. You would only save power by going full ARM, and optimizing software for that CPU. Reduce the bloat, the decades of history.
The problem is companies can't rewrite everything just because it'd be nice to have a less bloated, more optimal solution. Especially the vertical market and custom projects, where time of development trumps money spent on hyper-optimizing the product. In professional software (legal, financial, investment, automotive, government custom projects, pharmaceutical), you must have something quick and dirty but reliable that functions for decades, as opposed to the latest and greatest tech. I don't see Intel disappearing anytime soon on the Windows side. Heck, many companies still use fax and even floppy drives, because their system is so custom it'd cost more to rewrite than to maintain.
It is true that separate Intel and ARM MacBooks would require a lot of extra development and maintenance effort. I'm not sure they'd do it. It's more likely that they'll move a lot of services on ARM, while keeping the main system Intel. Encryption and video decoding have already been moved to ARM, but they could move more features there. Neural networks, JPEG compression, dozens of services could be moved to ARM. But that misses the whole point, because as long as the OS is running on Intel, you're not saving much power. You would only save power by going full ARM, and optimizing software for that CPU. Reduce the bloat, the decades of history.
The problem is companies can't rewrite everything just because it'd be nice to have a less bloated, more optimal solution. Especially the vertical market and custom projects, where time of development trumps money spent on hyper-optimizing the product. In professional software (legal, financial, investment, automotive, government custom projects, pharmaceutical), you must have something quick and dirty but reliable that functions for decades, as opposed to the latest and greatest tech. I don't see Intel disappearing anytime soon on the Windows side. Heck, many companies still use fax and even floppy drives, because their system is so custom it'd cost more to rewrite than to maintain.