Virtualizating Windows isn't very hard, even back to something like Windows 95.
On the other hand, only OSX 10.7+ are really easy to run in a VM, and .5 and .6 only work for servers, and anything before 10.5 isn't really going to be compatible with virtualization. That's 2007, so OSX lets you virtualize back about 13 years, and Windows you can go back almost 30 years. People even have Win 3.1 running in VMware.
This is probably due to the fact that there isn't powerpc virtualization software, but if you need to run osx software from before 2007, you're basically out of luck.
You can also virtualize windows from just about any OS you can imagine, Mac, Linux, Windows etc, while OSX virtualization has a hard requirement for running on Mac hardware.
There seems to be a misconception that you can only run 10.5 and later in a VM, but you can actually run OSX 10.4 Tiger fairly easily. This is the non server version. [1]
I was able to import almost everything from my old PPC computers. It's not completely virtualized because is using Rosetta and can not use Classic OS apps. But it is still extremely useful, and way faster than my PPC computers ever were.
>OSX virtualization has a hard requirement for running on Mac hardware.
If you aren't a stickler for Apple's terms of service (if you're doing this for business purposes, I suggest you should be), you can use a tool called macOS unlocker to patch VMWare Workstation to run macOS VMs. Runs great, though all VMWare products can only render display output for macOS in software mode.
Run a shady binary that seems to not have a certain author/website, as administrator, so it modifies VMWare binaries? A rather... curious approach, but for some reason common in Windows among e.g. gamers.
I've ran MacOS in VirtualBox iirc, without shady patches―though it probably was in Linux.
I have literally never heard of a "gamer" running shady binaries with administrator privilege in my entire life. Maybe you're thinking of the hacker culture of the 80s, but gamers today use launchers to manage downloading, installation and setup of software. Maybe you're thinking of software pirates using scene software as keygens or DRM-defeaters. I suppose that's common among kids who don't buy things (but I don't believe those tools run as admin).
It may be more common in Windows, but I would challenge that since Windows is basically free and runs on anything from a raspberry pi up, the vast majority of "hacky" stuff happens in Windows and Linux. Mac users buy very, very expensive hardware to do very specific tasks, and "hack around" is often not a good enough justification for the most expensive personal computers money buys.
I would also suggest that it in the Linux world where running random binaries as root is most common. Found some random repo that claims it's a fork of a good one with a bug fix? Build it and run it!
If the current version of OS X was backwards compatible with 10.0 - 10.4. It would still need both a PPC emulator and a 68K emulator since iOS 9 still had 68K code.
On the other hand, only OSX 10.7+ are really easy to run in a VM, and .5 and .6 only work for servers, and anything before 10.5 isn't really going to be compatible with virtualization. That's 2007, so OSX lets you virtualize back about 13 years, and Windows you can go back almost 30 years. People even have Win 3.1 running in VMware.
This is probably due to the fact that there isn't powerpc virtualization software, but if you need to run osx software from before 2007, you're basically out of luck.
You can also virtualize windows from just about any OS you can imagine, Mac, Linux, Windows etc, while OSX virtualization has a hard requirement for running on Mac hardware.