Having said that, please excuse my ignorance on system administration but, how does running a virtual machine that pretends to be a Linux/x64 box... on top of a real Linux/x64 box saves anybody at least some time? As a software developer who drank the Java kool-aid back in the 90, at least the "write once, run everywhere" mantra did make some kind of sense in those terms, but this other example is genuinely beyond me.
To me it has more to do with a tech company being able to put together an A-class team to serve a large number of customers that would not stand to pay the salary of a single full-time B-level IT guy if their business model depended on it.
To borrow someone else's words: https://blog.engineyard.com/2014/pets-vs-cattle
Or, in summary, it's a heck of a lot easier to instantiate a new instance of a machine from a snapshot than instantiate a new machine from a set of directions and some auto-config scripts.
I see some value in having a running system right now, instead of waiting for a long latency while the image is downloaded to real hardware... at least in some situations. However, is taking a permanent performance degradation of an order of magnitude worth that advantage?
Why does everybody ignore the obvious explanation, that you'd get from the mouth of any participant, for a convoluted one that only fits the criterium of political correctness?