There still aren’t too many Windows 10 PCs or laptops on the market with ARM-based processors, but folks who do have those machines will soon be able to run 64-bit x64 apps on them. Microsoft says it will at last roll out 64x emulation to Windows Insider testers in November.
Windows 10 has been able to emulate 32-bit x86 apps on ARM for a while, along with native 32-bit and 64-bit apps. Support for x64 emulation will allow those systems to run a far wider selection of software. As such, ARM-based Windows PCs and laptops will have far improved utility.