There's no support for x86_64 binaries. Windows 10 is still available in 32-bit editions and almost all apps are still available for 32-bit, so I don't think this is a big issue.

I assume any kernel drivers will need to be compiled for ARM64 though. This might not help corporate adoption--VPN client, 3rd party anti-virus/full disk encryption, etc.

Also one thing that is x86-64 only is WSL, the Windows Subsystem for Linux.