Yesterday I learned that virtual machines go all the way back to the 1960s (in this it's case multiple computers emulated on a bigger computer where a certain user gets access to the emulated computer but not the main one, and it was even called a virtual machine at the time)
As I say in the blog post, it's important to remember that most of what we have today in computing we also had in the 60s and 70s. It is just all much cheaper and faster now.