I would argue that the virtualization aspect is more important than the processiness of a container. Sure it's a process but it's a process that you've carefull

I would argue that the virtualization aspect is more important than the processiness of a container. Sure it's a process but it's a process that you've carefully controlled the resources it can access. You've put it in its own network namespace, you've rebuilt it's filesystem so it sees an entirely different / than the rest of the system, etc etc. If the process isn't checking, you can make it behave like it's in its own little world, with it's own kernel. Because of that, it's much more predictable than just a process. Saying it's a process is mostly correct, and saying it's a process tree is a guess even more correct I think they both miss the point.