And "EDIT: formatting" is now an additional layer, too :)

That's the layer that's argued about the most. :)

This process is called “Devops”

Are hypervisors and containers really abstractions though? All they do is manage access to the underlying resource.

A hypervisor definitely is; the "hardware" interface for a kernel running as a (performant) VM is different from the hardware interface for real hardware.

I think one could argue that containers aren't much of an abstraction for the running program itself, though, as you say. The place where containers provide an abstraction is at deployment time/process management time; the program itself has (essentially) the same API whether it's running in a container or not.