* Unmodified macOS guest VMs can run under ESXi (if you're reading this on macOS, you have an Apple-made VMXNet3 network adapter driver on your system--see /System/Library/Extensions/IONetworkingFamily.kext/Contents/PlugIns/AppleVmxnet3Ethernet.kext )
* Accelerated 3D has reasonable guest support, even as pure software. You wouldn't want to work in one of those guest VMs, but for any sort of build agent it should be fine, including opening i.e. Unity editor itself in-VM to diagnose something
Does anyone know where either of these things stand with Proxmox today?
I imagine macOS VM under Proxmox is basically a hackintosh with i.e. OpenCore as bootloader?