With macOS 15 Sequoia, Apple has added support for logging into iCloud in VMs:https://developer.apple.com/documentation/virtualization/using_icloud_with_macos_virtual_machines „In macOS 15 and later, Virtualization supports access to iCloud accounts and resources when running macOS in a virtual machine (VM) on Apple silicon. When you create a VM in macOS 15 from a macOS 15 software image (an .ipsw file) using a VZMacHardwareModel that you obtain from a VZMacOSRestoreImage, Virtualization configures an identity for the VM that it derives from security information in the host's Secure Enclave. Just as individual physical devices have distinct identities based on their Secure Enclaves, this identity is distinct from other VMs." This was not yet possible in Beta 1, but according to the release notes, it should now be possible with Beta 2: https://developer.apple.com/documentation/macos-release-notes/macos-15-release-notes#Virtualization Unfortunately, this still doesn't work for me. iCloud login still fails. The host Mac (MacBook Pro M1 Pro) and the VM are both on macOS 15 Sequoia Beta 2 and the VM was freshly installed from the image.
Apparently, the host needs to be Sequoia beta 3 as well ... check this article and the comments (https://eclecticlight.co/2024/07/12/sequoia-virtualisation-and-apple-id/).