Earlier quoted context omitted.
If containers had been a thing, many of the wild MS ideas of the early 2000s wouldn't have been actually crazy.
They were a thing, on mainframes, micro-computers, and a few selected UNIXes like the (shortly lived) Tru64 and HP-UX. My introduction to containers was HP-UX Vaults.
But there wouldn't have been the hardware, resources, or depth of support available for the end user in the 2000s. There are still non-technical folks I deal w/ at work that don't get what a VM is...