Half of these exist because I was bored once.
The Windows 10 and MacOS ones are GPU passthrough enabled and what I occasionally use if I have to use a Windows or Mac application. Windows 7 is also GPU enabled, but is more a nostalgia thing than anything.
I think my PopOS VM was originally installed for fun, but I used it along with my Arch Linux, Debian 12 and Testing (I run Testing on host, but I wanted a fresh environment and was too lazy to spin up a Docker or chroot), Ubuntu 23.10 and Fedora to test various software builds and bugs, as I don't like touching normal Ubuntu unless I must.
The Windows Server 2022 one is one I recently spun up to mess with Windows Docker Containers (I have to port an app to Windows, and was looking at that for CI). That all become moot when I found out Github's CI doesn't support Windows Docker containers despite supporting Windows runners (The organization I'm doing it for uses Github, so I have to use it).
That’s a beast of a Mac. Wake on lan is your friend. I have the same problem with my Threadripper. I wrote a script that issues a WOL command to either start/unsuspend my Ubuntu machine so I can turn it off when not in use. It’s probably $70/month difference for me. Most of my virtualization is on Linux but I’ve moved away from VM Ware because QEMU/KVM has worked so well for me. You should check out UTM on the Mac App Store and see if that solves any of your problems.
ETA: https://mac.getutm.app/
Man this thread has taught me all sorts of things. I will definitely check out UTM. Thanks for that!!