But that is the whole point! It's not about the technology or the isolation (while running). It's about the ability to simplify the generation of a new set of containers. Yes that's mostly tooling. But tooling is the single most important difference between something that's cool and something that's useful!
We moved from "here is an (incomplete) description of what I did", which rounds to "please guess all the previous stuff that I did to my environment, before even starting to work on getting my instructions to work" to "download this binary and execute these 5 lines". The incompleteness problem of the description of _the actual thing you want to do_ hasn't gone away, but the largely not even mentioned description of where you have to do the thing... that has been replaced by Dockerfiles
You seem not to have worked with the VM tools that do the same thing as a Dockerfile. Had you, you would realize that your points are invalid and I can have the same guarantees with VM as containers
If you think Dockerfiles are great, then you haven't hit the day 2 problems yet or explored the better alternatives for defining containers.
Also, the whole point of the original post is to point out that what you are saying is not magically true for containers
That's exactly what I have been saying, though. Prior to Docker, there was nothing like Dockerfiles or OCI images. The closest thing I can think of was Vagrant, but it's missing a lot of what makes Docker good.
The reason why containers are good is entirely about the concepts, NOT the actual engine or technologies. Again, you can literally run OCI images in a virtual machine; Ignite will run them in a KVM. That's as literal as you can get.
Docker existed and did a lot of the same things it does today in 2013.
The ONLY thing docker did was make a small amount of questionable UX around the low-level container primitives. They did not invent anything, definitely not containers. I could share VM images before Docker, nothing new there... the concepts all existed before containers.
You can literally run... anything... on a VM, why make a point about being able to run OCI images? This is like a no-op.
We moved from "here is an (incomplete) description of what I did", which rounds to "please guess all the previous stuff that I did to my environment, before even starting to work on getting my instructions to work" to "download this binary and execute these 5 lines". The incompleteness problem of the description of _the actual thing you want to do_ hasn't gone away, but the largely not even mentioned description of where you have to do the thing... that has been replaced by Dockerfiles