Last year, Microsoft released the first preview of x64 emulation for ARM64 devices to Windows Insiders. x64 emulation allowed Windows 10 ARM users to install x64 apps including apps like Autodesk Sketchbook, games like Rocket League. These apps and games benefit from having more memory when run as 64-bit emulated apps.
Today, Microsoft announced the general availability of x64 emulation in Windows 11. Yes, x64 emulation is available only on PCs running Windows 11 on ARM. Even though x64 emulation preview was available on Windows 10 on ARM devices, the final version will require Windows 11 OS.